fix: restore La Roca 1.68 plugin compatibility

[teseo]

Intent

Release github.com/thellmwhisperer/roca-firstmate so La Roca 1.68 no longer skips it. Strict validation currently skips this plugin because the semantic fragment omits table seats (Nerve added seats; packaged plugin.json does not declare them). Complete the semantic fragment so it matches the database, including seats, PLUS the pending VECTOR declaration. Vector surfaces are prose plus task text, as frozen: the five family content columns (working_set_versions, archive_versions, task_state_versions, operational_doc_versions, task_artifact_versions). Selectivity is embeddings-only, never ingest: do not add an ingest verb or capability. Do not install this plugin onto any live captain La Roca install. Public PR must contain no personal paths, UUIDs, or corpus counts. Ship a green non-draft PR and arm auto-merge when CI is green; do not merge red.

What Changed

• Complete the v1.68 semantic manifest with the missing seats table and wakeups.handled_generation, then bump the plugin version and checksum.
• Declare embeddings-only vector surfaces for the content columns of all five versioned Markdown families, without adding ingest behavior.
• Add manifest/database parity and vector-selectivity coverage, and update documentation for the v1.68 contract.

Risk Assessment

✅ Low: The change is well-bounded and conforms to the La Roca 1.68 manifest contract, including all five vector surfaces, seats coverage, and no ingest capability.

Testing

Targeted package tests passed, La Roca v1.68.0’s real strict consumer path accepted 0.4.0 with seats and exactly five embeddings-only VECTOR surfaces, and a hermetic CLI install/update reported it as data-only; the changed-line privacy scan was clean, no live La Roca installation was touched, and all transient worktree artifacts were removed.

Evidence: La Roca 1.68 consumer validation

La Roca 1.68 accepted roca-firstmate 0.4.0 without skipping it; all 11 semantic tables include seats; VECTOR exposes exactly five content columns; ingest is absent.

=== RUN   TestRocaFirstmate168ConsumerContract
    roca_firstmate_acceptance_test.go:79: La Roca 1.68 accepted roca-firstmate 0.4.0 without skipping it
    roca_firstmate_acceptance_test.go:80: strict semantic declaration covers all 11 database tables, including seats
    roca_firstmate_acceptance_test.go:81: vector registry exposes exactly five family content columns; ingest is absent
--- PASS: TestRocaFirstmate168ConsumerContract (0.00s)
PASS
ok  	github.com/thellmwhisperer/la-roca/internal/provider/plugin	0.290s

Evidence: Hermetic plugin update

{"action":"updated","name":"roca-firstmate","risk":"data-only","version":"0.4.0"}

{
  "action": "updated",
  "checksum": "b80300c6e49a38928fe7275673fc0b1d8f143d7d05c226002e62aa747de53067",
  "name": "roca-firstmate",
  "risk": "data-only",
  "version": "0.4.0"
}

Pipeline

Updates from git push no-mistakes

✅ **intent** - passed

✅ No issues found.

✅ **Rebase** - passed

✅ No issues found.

✅ **Review** - passed

✅ No issues found.

✅ **Test** - passed

✅ No issues found.

• Inspected git diff 72cb10cd334aadeaa0f71d23f7dc4fa529842ccb..83f53ad34bdb7ca4a678e453e1146b526e12790b and confirmed the clean checkout targets commit 83f53ad34bdb7ca4a678e453e1146b526e12790b.
• go test ./schema -run 'TestPluginManifestDescribesTheShippedDatabase|TestPluginManifestDeclaresEmbeddingsOnlyVectorSurfaces|TestChecksumsCoverExactlyTheInstallPayload|TestShippedDatabaseHasNoMirroredRows' -v
• ROCA_FIRSTMATE_UNDER_TEST="$PWD/../.." go test ./internal/provider/plugin -run '^TestRocaFirstmate168ConsumerContract$' -v against La Roca v1.68.0 production validation code.
• Installed and updated the package with roca v1.68.0 using an isolated HOME; the initial expected feature-flag setup error was fixed by enabling features.plugins only in that hermetic environment.
• Scanned added public lines for personal paths, UUIDs, and corpus-count markers; none were present.
• Removed the downloaded La Roca source, hermetic installation, configuration, and other transient worktree artifacts; final git status --short was empty.

✅ **Document** - passed

✅ No issues found.

✅ **Lint** - passed

✅ No issues found.

✅ **Push** - passed

✅ No issues found.