Fix PromptTemplateSeeder: default summarizer to DeepSeek + stop clobbering operator model overrides

You are being dispatched from flower Brief #162: Fix PromptTemplateSeeder: default summarizer to DeepSeek + stop clobbering operator model overrides

Recall pointer:
- Use recall_brief with id 162 for the full folder if you need provenance.

Target:
- project: flower (/Users/mikeferrara/Documents/code/flower)
- branch: flower/162-seeder-deepseek-default
- worktree: not specified
- kind: fresh

Current brief spec:
## Objective
Make the segment_summary summarizer default to DeepSeek (OpenRouter/json) and stop the seeder from silently reverting an operator-chosen provider/model on re-seed.

## Problem (incident 2026-07-03, root cause of feedback #74)
`database/seeders/PromptTemplateSeeder.php` (L28-29) hardcodes the segment_summary default as provider=anthropic, model=claude-opus-4-8, via updateOrCreate keyed on 'segment_summary.default'. So ANY re-seed overwrites the live prompt_templates row (id=1) back to Opus. On 2026-07-03 15:41 a re-seed (likely during DB backup/restore work, commit fa5465d) clobbered the operator's deliberate deepseek/deepseek-v4-flash selection (set 2026-06-29 via Config UI, session 737) back to Opus. With the ANTHROPIC_API_KEY account out of credits, every SegmentSession job then threw InsufficientCreditsException (Sentry FLOWER-B) → sessions ingested but never segmented/indexed (operator saw this as #74 "Ingest broken?"). Ops applied the RUNTIME fix (reverted row id=1 to openrouter/deepseek-v4-flash + `queue:retry all`, failed_jobs 57→0, pipeline recovered). THIS brief is the durable code fix.

## Fix
1. Change the seeder's segment_summary default to provider=openrouter, model=deepseek/deepseek-v4-flash (json mode) — the intended production default. Prefer sourcing it from config (one source of truth, e.g. a `default` flag on a config('flower.summarize.models') entry) rather than a second hardcode.
2. Make the seed NON-CLOBBERING for provider/model: on re-seed, do NOT overwrite an existing row's provider/model (operator override wins) — create-only for those two fields, while still updating code-owned prompt body/schema fields.
3. Address the fallback: config/ai.php `'default' => env('AI_DEFAULT_PROVIDER','anthropic')` with AI_DEFAULT_PROVIDER unset means a blank-provider template silently falls back to anthropic. Either set AI_DEFAULT_PROVIDER=openrouter in .env(.example) or ensure the summary template always carries an explicit provider.

## Constraints / non-goals
- Don't change the live prompt text/schema seeding behavior, only the provider/model default + the clobber-guard.
- Add a test: re-running the seeder must NOT change an operator-set provider/model.

## Definition of done
Seeder default = deepseek; re-seed preserves an operator-set provider/model; test covers the non-clobber; verified `db:seed --class=PromptTemplateSeeder` on a row set to a custom model leaves provider/model intact.

Recent/key trace events:
[1] participant_joined flower-ops: (no body)
[2] note_added flower-ops: ## Objective
Make the segment_summary summarizer default to DeepSeek (OpenRouter/json) and stop the seeder from silently reverting an operator-chosen provider/model on re-seed.

## Problem (incident 2026-07-03, root cause of feedback #74)
`database/seeders/PromptTemplateSeeder.php` (L28-29) hardcodes the segment_summary default as provider=anthropic, model=claude-opus-4-8, via updateOrCreate keyed on 'segment_summary.default'. So ANY re-seed overwrites the live prompt_templates row (id=1) back to Opus. On 2026-07-03 15:41 a re-seed (likely during DB backup/restore work, commit fa5465d) clobbered the operator's deliberate deepseek/deepseek-v4-flash selection (set 2026-06-29 via Config UI, session 737) back to Opus. With the ANTHROPIC_API_KEY account out of credits, every SegmentSession job then threw InsufficientCreditsException (Sentry FLOWER-B) → sessions ingested but never segmented/indexed (operator saw this as #74 "Ingest broken?"). Ops applied the RUNTIME fix (reverted row id=1 to openrouter/deepseek-v4-flash + `queue:retry all`, failed_jobs 57→0, pipeline recovered). THIS brief is the durable code fix.

## Fix
1. Change the seeder's segment_summary default to provider=openrouter, model=deepseek/deepseek-v4-flash (json mode) — the intended production default. Prefer sourcing it from config (one source of truth, e.g. a `default` flag on a config('flower.summarize.models') entry) rather than a second hardcode.
2. Make the seed NON-CLOBBERING for provider/model: on re-seed, do NOT overwrite an existing row's provider/model (operator override wins) — create-only for those two fields, while still updating code-owned prompt body/schema fields.
3. Address the fallback: config/ai.php `'default' => env('AI_DEFAULT_PROVIDER','anthropic')` with AI_DEFAULT_PROVIDER unset means a blank-provider template silently falls back to anthropic. Either set AI_DEFAULT_PROVIDER=openrouter in .env(.example) or ensure the summary template always carries an explicit provider.

## Constraints / non-goals
- Don't change the live prompt text/schema seeding behavior, only the provider/model default + the clobber-guard.
- Add a test: re-running the seeder must NOT change an operator-set provider/model.

## Definition of done
Seeder default = deepseek; re-seed preserves an operator-set provider/model; test covers the non-clobber; verified `db:seed --class=PromptTemplateSeeder` on a row set to a custom model leaves provider/model intact.
[3] plan_proposed flower-ops: ## Objective
Make the segment_summary summarizer default to DeepSeek (OpenRouter/json) and stop the seeder from silently reverting an operator-chosen provider/model on re-seed.

## Problem (incident 2026-07-03, root cause of feedback #74)
`database/seeders/PromptTemplateSeeder.php` (L28-29) hardcodes the segment_summary default as provider=anthropic, model=claude-opus-4-8, via updateOrCreate keyed on 'segment_summary.default'. So ANY re-seed overwrites the live prompt_templates row (id=1) back to Opus. On 2026-07-03 15:41 a re-seed (likely during DB backup/restore work, commit fa5465d) clobbered the operator's deliberate deepseek/deepseek-v4-flash selection (set 2026-06-29 via Config UI, session 737) back to Opus. With the ANTHROPIC_API_KEY account out of credits, every SegmentSession job then threw InsufficientCreditsException (Sentry FLOWER-B) → sessions ingested but never segmented/indexed (operator saw this as #74 "Ingest broken?"). Ops applied the RUNTIME fix (reverted row id=1 to openrouter/deepseek-v4-flash + `queue:retry all`, failed_jobs 57→0, pipeline recovered). THIS brief is the durable code fix.

## Fix
1. Change the seeder's segment_summary default to provider=openrouter, model=deepseek/deepseek-v4-flash (json mode) — the intended production default. Prefer sourcing it from config (one source of truth, e.g. a `default` flag on a config('flower.summarize.models') entry) rather than a second hardcode.
2. Make the seed NON-CLOBBERING for provider/model: on re-seed, do NOT overwrite an existing row's provider/model (operator override wins) — create-only for those two fields, while still updating code-owned prompt body/schema fields.
3. Address the fallback: config/ai.php `'default' => env('AI_DEFAULT_PROVIDER','anthropic')` with AI_DEFAULT_PROVIDER unset means a blank-provider template silently falls back to anthropic. Either set AI_DEFAULT_PROVIDER=openrouter in .env(.example) or ensure the summary template always carries an explicit provider.

## Constraints / non-goals
- Don't change the live prompt text/schema seeding behavior, only the provider/model default + the clobber-guard.
- Add a test: re-running the seeder must NOT change an operator-set provider/model.

## Definition of done
Seeder default = deepseek; re-seed preserves an operator-set provider/model; test covers the non-clobber; verified `db:seed --class=PromptTemplateSeeder` on a row set to a custom model leaves provider/model intact.
[4] status_change flower-ops: (no body)

Recommended linked context:
{
    "todos": [],
    "scratchpads": []
}

Execution notes:
- Treat the brief as the source of truth.
- Keep work scoped to this dispatch request.
- Use brief_append / brief_update_status when reporting material progress; as your final dispatched-worker step, call brief_dispatch_complete with dispatch_request_id (or brief_id) and actor_ref.
- Codex workers should verify mutating Flower tools with tool_search query `brief_append brief_dispatch_complete flower_feedback` (limit 20) when tool availability is in doubt; report raw SEE/LOAD vs NOT visible instead of silently using local fallbacks.
- Add a git commit trailer `Brief: #162` to every commit for this brief so flower can exact-link commits back to the brief.