feat(llm-aliases): M5 — migrate consumers to MANA_LLM aliases

Final milestone of docs/plans/llm-fallback-aliases.md. Every backend
caller now requests models via the `mana/<class>` alias system instead
of hardcoded `ollama/...` strings. mana-llm resolves aliases through
`services/mana-llm/aliases.yaml` with health-aware fallback (M3) and
emits resolved-model + fallback metrics (M4).

SSOT moved to `packages/shared-ai/src/llm-aliases.ts` so apps/api,
apps/mana/apps/web, and services/mana-ai all import the same
`MANA_LLM` constant via the existing `@mana/shared-ai` workspace
dependency. Three additional sites (memoro-server, mana-events,
mana-research) inline the alias string with a SSOT comment because
they don't pull @mana/shared-ai today.

Migrated 14 sites across 10 files:
- apps/api: writing(LONG_FORM), comic(STRUCTURED), context(FAST_TEXT),
  food(VISION), plants(VISION), research orchestrator (3 tiers
  collapsed to STRUCTURED+FAST_TEXT/LONG_FORM)
- apps/mana/apps/web: voice/parse-task + parse-habit (STRUCTURED)
- services/mana-ai: planner llm-client + tick.ts (REASONING)
- services/mana-events: website-extractor (STRUCTURED, inlined)
- services/mana-research: mana-llm client (FAST_TEXT, inlined)
- apps/memoro/apps/server: ai.ts (FAST_TEXT, inlined)

Legacy env-vars removed: WRITING_MODEL, COMIC_STORYBOARD_MODEL,
VISION_MODEL, MANA_LLM_DEFAULT_MODEL. The chain in aliases.yaml is
now the single tuning surface; SIGHUP reloads it without redeploys.

New `scripts/validate-llm-strings.mjs` regex-scans 2538 files for
hardcoded `<provider>/<model>` strings and fails the build if any
land outside the SSOT or the explicitly-allowed paths (image-gen
modules, model-inspector code, this validator itself, the registry).
Wired into `validate:all` next to the i18n + theme validators.

Verified: `pnpm validate:llm-strings` clean, `pnpm --filter @mana/api
type-check` clean, `pnpm --filter @mana/ai-service type-check`
clean. Web type-check has 2 pre-existing errors in
SettingsSidebar.svelte (i18n MessageFormatter type drift, last
touched in 988c17a67 — unrelated to this work).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/api/src/modules/research/orchestrator.ts

@@ -18,9 +18,15 @@
 import { eq } from 'drizzle-orm';
 import { db, researchResults, sources, type ResearchDepth } from './schema';
 import { llmJson, llmStream, LlmError } from '../../lib/llm';
+import { MANA_LLM } from '@mana/shared-ai';
 import { webSearch, bulkExtract, type SearchHit, SearchError } from '../../lib/search';
 
 // ─── Depth configuration ────────────────────────────────────
+//
+// `planModel` is always `STRUCTURED` (the planner emits JSON).
+// `synthModel` varies by depth: `quick` runs through `FAST_TEXT` for a
+// terse summary, `standard`/`deep` use `LONG_FORM` for richer prose.
+// Concrete provider/model selection lives in services/mana-llm/aliases.yaml.
 
 interface DepthConfig {
 	subQueryCount: number;
@@ -39,8 +45,8 @@ const DEPTH_CONFIG: Record<ResearchDepth, DepthConfig> = {
 		maxSources: 5,
 		extract: false,
 		categories: ['general'],
-		planModel: 'ollama/gemma3:4b',
-		synthModel: 'ollama/gemma3:4b',
+		planModel: MANA_LLM.STRUCTURED,
+		synthModel: MANA_LLM.FAST_TEXT,
 	},
 	standard: {
 		subQueryCount: 3,
@@ -48,8 +54,8 @@ const DEPTH_CONFIG: Record<ResearchDepth, DepthConfig> = {
 		maxSources: 15,
 		extract: true,
 		categories: ['general', 'news'],
-		planModel: 'ollama/gemma3:4b',
-		synthModel: 'ollama/gemma3:12b',
+		planModel: MANA_LLM.STRUCTURED,
+		synthModel: MANA_LLM.LONG_FORM,
 	},
 	deep: {
 		subQueryCount: 6,
@@ -57,8 +63,8 @@ const DEPTH_CONFIG: Record<ResearchDepth, DepthConfig> = {
 		maxSources: 30,
 		extract: true,
 		categories: ['general', 'news', 'science', 'it'],
-		planModel: 'ollama/gemma3:12b',
-		synthModel: 'ollama/gemma3:12b',
+		planModel: MANA_LLM.STRUCTURED,
+		synthModel: MANA_LLM.LONG_FORM,
 	},
 };