Standalone Shonar Desktop: vendor portable sources + local engine; decouple from ~/Projects/Shonar

- shared/ = portable Android-origin sources vendored from deferred/desktop-server
  (app/build.gradle.kts srcDir repointed; PlaybackController.kt excluded as Android-only)
- backend/ = bundled-lite engine (SQLite + inline queue); .venv symlinked from the
  old checkout, PYTHONPATH pins THIS backend's code over any editable install
- repoRoot() resolves this project dir (env SHONAR_REPO still wins); desktop-dev.sh
  watches shared/ + backend/
- Verified: :app:compileKotlin + :app:test green (23 tests); engine boots on :8010,
  self-migrates, /healthz ok

backend/migrations/versions/fts0000000001_fts_columns.py

@@ -0,0 +1,86 @@
+"""full-text search columns (PostgreSQL tsvector)
+
+Revision ID: fts0000000001
+Revises: 0c938663a363
+
+Generated (STORED) tsvector columns + GIN indexes for search across title,
+transcript text, summary content, tags, and action items. The SearchBackend
+protocol keeps this swappable for Meilisearch/OpenSearch later.
+"""
+from __future__ import annotations
+
+from collections.abc import Sequence
+
+from alembic import op
+
+revision: str = "fts0000000001"
+down_revision: str | None = "8d51af959ae4"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    # tsvector is PostgreSQL-only. On SQLite (desktop bundled engine) full-
+    # text search is handled outside the DB (the app scans report files),
+    # so this migration is a no-op.
+    if op.get_context().dialect.name != "postgresql":
+        return
+    # recordings: title + notes + tag names are indexed; transcript/summary
+    # contribute via their own tables (joined at query time).
+    op.execute(
+        """
+        ALTER TABLE recordings
+          ADD COLUMN search_vector tsvector
+          GENERATED ALWAYS AS (
+            setweight(to_tsvector('simple', coalesce(title, '')), 'A') ||
+            setweight(to_tsvector('simple', coalesce(notes, '')), 'B')
+          ) STORED;
+        """
+    )
+    op.execute("CREATE INDEX ix_recordings_search ON recordings USING GIN (search_vector);")
+
+    op.execute(
+        """
+        ALTER TABLE transcripts
+          ADD COLUMN search_vector tsvector
+          GENERATED ALWAYS AS (
+            setweight(to_tsvector('simple', coalesce(text, '')), 'B')
+          ) STORED;
+        """
+    )
+    op.execute("CREATE INDEX ix_transcripts_search ON transcripts USING GIN (search_vector);")
+
+    # summary content JSON -> extractive text for FTS. Generated columns
+    # forbid subqueries/set-returning functions, so we index the JSON body
+    # with punctuation stripped (covers key_points/decisions/action_items/
+    # questions) plus weighted short/detailed fields.
+    op.execute(
+        """
+        ALTER TABLE summaries
+          ADD COLUMN search_vector tsvector
+          GENERATED ALWAYS AS (
+            setweight(to_tsvector('simple', coalesce(content->>'short', '')), 'A') ||
+            setweight(to_tsvector('simple', coalesce(content->>'detailed', '')), 'B') ||
+            setweight(
+              to_tsvector('simple',
+                regexp_replace(coalesce(content::text, ''), '[\\[\\]{}"]', ' ', 'g')), 'C')
+          ) STORED;
+        """
+    )
+    op.execute("CREATE INDEX ix_summaries_search ON summaries USING GIN (search_vector);")
+
+    op.execute(
+        """
+        ALTER TABLE tags ADD COLUMN IF NOT EXISTS search_vector tsvector
+          GENERATED ALWAYS AS (to_tsvector('simple', coalesce(name, ''))) STORED;
+        """
+    )
+    op.execute("CREATE INDEX ix_tags_search ON tags USING GIN (search_vector);")
+
+
+def downgrade() -> None:
+    if op.get_context().dialect.name != "postgresql":
+        return
+    for table in ("tags", "summaries", "transcripts", "recordings"):
+        op.execute(f"DROP INDEX IF EXISTS ix_{table}_search;")
+        op.execute(f"ALTER TABLE {table} DROP COLUMN IF EXISTS search_vector;")