PR3-C: v2-only oclmap (drop allCandidates + legacy load/save)

[paynejd]

Summary

Closes OpenConceptLab/ocl_issues#2541. Companion to the v1->v2 migration script in oclmap#34.

Draft until the v1->v2 migration runs against prod in the maintenance window. Until then, this code reads empty for every project (no `mapper_schema_version: 2` marker on existing blobs).

After the migration + this PR ship together, oclmap reads/writes only the v2 wire format. ~−267 LOC across `MapProject.jsx` + `normalizers.js` + one deleted test file.

What changes

Change	Effect
`onSave` writes v2 directly (`mapper_schema_version: 2` + `concept_definitions` + `rows`)	Replaces the `_getCandidates` flatten of `allCandidates`
`fetchAndSetProject` deserializes v2 directly into `rowMatchState` + `conceptCache`	Replaces the legacy `_allCandidates` hydration + `normalizeLegacyAllCandidates` backfill
Deleted: post-load re-normalize-on-canonical-resolve effect	Was a workaround for the legacy load missing the live canonical; v2 load captures it at save time
Deleted: `allCandidates` state + `allCandidatesRef` + ~10 `setAllCandidates` writes	Single source of truth is `rowMatchState`
Translated: 49 `allCandidatesRef.current` readers	Read from `rowMatchState` + `conceptCache` directly, or via the small `derivedAllCandidates()` projection helper for CSV-export readers
Deleted: `normalizeLegacyAllCandidates` from `normalizers.js` + its test file	Wire format is v2 only
Deleted: `UNIFIED_MODEL_ENABLED` flag	Always true since PR2b
Net	−267 LOC

Test plan

• `npm test` — 135/135 (the 12 legacy-path tests were in the deleted `normalizeLegacyAllCandidates.test.js`).
• `npm run eslint` clean on touched files.
• `npm run build` compiles successfully.
• Browser smoke test before merge (during the maintenance window):
  • Load an existing migrated v2 project — candidates render identically vs. pre-migration.
  • Run a per-row match — results appear in the candidates list and quality view.
  • Save — the new candidates blob in the DB is v2-shaped.
  • Reload — state restored identically.
  • CSV export — produces the expected per-algo columns with scores.
  • Bridge cascade rendering — bridge_child rows show cascade-target details.
  • AI Assistant — buildV2RecommendationPayload still produces the same payload shape (no fallback path; reads only from `rowMatchState`).

Notes for review

• The `derivedAllCandidates()` helper at MapProject.jsx ~L3078 is intentional pragmatism: it produces the legacy `{algoId: [{row, results}, ...]}` shape from `rowMatchState` + `conceptCache` on demand, so CSV-export readers don't have to be refactored in this PR. The whole helper is a candidate for follow-up cleanup once each reader is rewritten to consume `rowMatchState` directly.
• The migration script (oclmap#34) imports `normalizeLegacyAllCandidates`. This PR deletes that function — so the script becomes non-functional after this merges. The script's job is one-shot (the maintenance-window migration). Its README documents this lifecycle.

🤖 Generated with Claude Code

[paynejd]

Review of the two follow-up commits (21f42b7, 7e857a5). Both are correct and fix real bugs — setConfigure(false) removes a dangling loadProjectContext ReferenceError on project load, and the conceptBelongsToTargetRepo relative-URL fallback recovers candidates whose migrated/derived canonical no longer equals the live target_repo.canonical_url. Tests 136/136, eslint clean.

Four polish suggestions below (none blocking). A and D are quick wins; B+C align an inconsistent guard and fix a now-false comment.

[paynejd]

A — empty-string canonicals compare equal (latent). normalizeCanonicalUrl('') returns '/', not '', which defeats the !== '' guard in canonicalUrlsEqual — so canonicalUrlsEqual('', '') is true, and two concepts with empty canonical URLs are wrongly treated as target-repo members. Verified by exercising the helper directly. Mirror normalizeRelativeUrl's empty-string guard; after this the two helpers are identical and could be merged into one.

Suggested change

	if(typeof url !== 'string') return ''
	if(typeof url !== 'string' || url === '') return ''

[paynejd]

D — dead check. oclUrl is already coalesced to a string by || '' on the line above, so typeof oclUrl === 'string' is always true. Drop it.

Suggested change

	return relativeUrl !== '' && typeof oclUrl === 'string' && oclUrl.startsWith(relativeUrl)
	return relativeUrl !== '' && oclUrl.startsWith(relativeUrl)

[paynejd]

B — stale comment + C — guard inconsistency. This comment now contradicts the code: the comparison is no longer exact — that's the whole point of conceptBelongsToTargetRepo's relative-URL fallback. And this guard checks only !targetCanonical, whereas the sibling guards in qualityRowViews, Concept.isMappable, and pickTopRowView use !targetCanonical && !targetRelativeUrl. So if canonical is ever absent but relative_url is present, the table Action column would render MapButtons on every row (including bridge intermediaries). Align both:

Suggested change

	// ConceptDefinition.reference.url, so the comparison is exact.
	const isTargetRepoView = (view) => {
	if(!targetCanonical) return true
	// ConceptDefinition.reference.url in the common case; the comparison also
	// tolerates canonical drift via the OCL relative-URL fallback below.
	const isTargetRepoView = (view) => {
	if(!targetCanonical && !targetRelativeUrl) return true