fix: 4 API bugs found by integration tests

1. tags.owner_id column missing — Migration 0105 adds owner_id to tags table
2. contacts trigger first_name vs firstname — Migration 0105 recreates
   unified_search TSV trigger with correct column names (firstname, surname, etc.)
3. create_webhook() missing is_system_admin param — Add to webhook_service.py
4. Missing GET /api/v1/search endpoint — Add to unified_search/routes.py
   with shared _do_search() helper for GET+POST

Alembic head: 0104 → 0105

alembic/versions/0105_fix_tags_owner_id_and_contacts_trigger.py

@@ -0,0 +1,153 @@
+"""Fix tags.owner_id missing column and contacts_tsv_trigger column mismatch.
+
+Bug 1: tags.owner_id — Migration 0102 tried to add owner_id to tags but only
+if the table existed at that point. If the tags table was created later (by
+plugin migration), owner_id was never added. This migration ensures owner_id
+exists on the tags table.
+
+Bug 2: contacts_tsv_trigger — The unified_search plugin migration 0001 created
+a trigger function referencing NEW.first_name, NEW.last_name, NEW.email,
+NEW.phone, NEW.mobile, NEW.notes. After migration 0021 unified contacts,
+the columns are named firstname, surname, email_1, phone_1, phone_2,
+projectnote. The trigger must be recreated with correct column names.
+
+Revision ID: 0105
+"""
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects.postgresql import UUID as PGUUID
+
+revision = "0105"
+down_revision = "0104"
+branch_labels = None
+depends_on = None
+
+
+def _table_exists(conn, table_name: str) -> bool:
+    result = conn.execute(
+        sa.text(
+            "SELECT EXISTS (SELECT 1 FROM information_schema.tables "
+            "WHERE table_name = :name)"
+        ),
+        {"name": table_name},
+    )
+    return result.scalar()
+
+
+def _column_exists(conn, table_name: str, column_name: str) -> bool:
+    result = conn.execute(
+        sa.text(
+            "SELECT EXISTS (SELECT 1 FROM information_schema.columns "
+            "WHERE table_name = :table AND column_name = :col)"
+        ),
+        {"table": table_name, "col": column_name},
+    )
+    return result.scalar()
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+
+    # ── Bug 1: Add owner_id to tags table if missing ──
+    if _table_exists(conn, "tags"):
+        if not _column_exists(conn, "tags", "owner_id"):
+            op.add_column(
+                "tags",
+                sa.Column(
+                    "owner_id",
+                    PGUUID(as_uuid=True),
+                    sa.ForeignKey("users.id", ondelete="SET NULL"),
+                    nullable=True,
+                ),
+            )
+            op.create_index(
+                "ix_tags_owner_id",
+                "tags",
+                ["owner_id"],
+            )
+            print("[0105] Added owner_id to tags table")
+        else:
+            print("[0105] tags.owner_id already exists — skipping")
+    else:
+        print("[0105] tags table does not exist — skipping")
+
+    # ── Bug 2: Recreate contacts_tsv_trigger with correct column names ──
+    if _table_exists(conn, "contacts"):
+        # Drop old trigger and function
+        op.execute("DROP TRIGGER IF EXISTS contacts_tsv_update ON contacts")
+        op.execute("DROP FUNCTION IF EXISTS contacts_tsv_trigger()")
+
+        # Recreate trigger function with current column names
+        # Contacts table after migration 0021 uses: firstname, surname, email_1,
+        # email_2, phone_1, phone_2, name, displayname, code, mailing_city,
+        # mailing_postalcode, tags, projectnote
+        op.execute(
+            """
+            CREATE OR REPLACE FUNCTION contacts_tsv_trigger() RETURNS trigger AS $$
+            BEGIN
+                NEW.search_tsv :=
+                    setweight(to_tsvector('pg_catalog.german',
+                        coalesce(NEW.name, '') || ' ' || coalesce(NEW.displayname, '') ||
+                        ' ' || coalesce(NEW.firstname, '') || ' ' || coalesce(NEW.surname, '')), 'A') ||
+                    setweight(to_tsvector('pg_catalog.german',
+                        coalesce(NEW.email_1, '') || ' ' || coalesce(NEW.email_2, '')), 'B') ||
+                    setweight(to_tsvector('pg_catalog.german',
+                        coalesce(NEW.phone_1, '') || ' ' || coalesce(NEW.phone_2, '')), 'C') ||
+                    setweight(to_tsvector('pg_catalog.german',
+                        coalesce(NEW.code, '') || ' ' || coalesce(NEW.mailing_city, '') ||
+                        ' ' || coalesce(NEW.mailing_postalcode, '') || ' ' || coalesce(NEW.tags, '') ||
+                        ' ' || coalesce(NEW.projectnote, '')), 'D');
+                RETURN NEW;
+            END;
+            $$ LANGUAGE plpgsql;
+            """
+        )
+
+        # Recreate trigger
+        op.execute(
+            """
+            CREATE TRIGGER contacts_tsv_update
+                BEFORE INSERT OR UPDATE ON contacts
+                FOR EACH ROW EXECUTE FUNCTION contacts_tsv_trigger();
+            """
+        )
+        print("[0105] Recreated contacts_tsv_trigger with correct column names")
+    else:
+        print("[0105] contacts table does not exist — skipping trigger fix")
+
+
+def downgrade() -> None:
+    conn = op.get_bind()
+
+    # Restore old trigger function (with incorrect column names for rollback)
+    if _table_exists(conn, "contacts"):
+        op.execute("DROP TRIGGER IF EXISTS contacts_tsv_update ON contacts")
+        op.execute("DROP FUNCTION IF EXISTS contacts_tsv_trigger()")
+        op.execute(
+            """
+            CREATE OR REPLACE FUNCTION contacts_tsv_trigger() RETURNS trigger AS $$
+            BEGIN
+                NEW.search_tsv :=
+                    setweight(to_tsvector('pg_catalog.german', coalesce(NEW.first_name, '') || ' ' || coalesce(NEW.last_name, '')), 'A') ||
+                    setweight(to_tsvector('pg_catalog.german', coalesce(NEW.email, '')), 'B') ||
+                    setweight(to_tsvector('pg_catalog.german', coalesce(NEW.phone, '') || ' ' || coalesce(NEW.mobile, '')), 'C') ||
+                    setweight(to_tsvector('pg_catalog.german', coalesce(NEW.notes, '')), 'D');
+                RETURN NEW;
+            END;
+            $$ LANGUAGE plpgsql;
+            """
+        )
+        op.execute(
+            """
+            CREATE TRIGGER contacts_tsv_update
+                BEFORE INSERT OR UPDATE ON contacts
+                FOR EACH ROW EXECUTE FUNCTION contacts_tsv_trigger();
+            """
+        )
+
+    # Remove owner_id from tags
+    if _table_exists(conn, "tags") and _column_exists(conn, "tags", "owner_id"):
+        op.drop_index("ix_tags_owner_id", table_name="tags")
+        op.drop_column("tags", "owner_id")
+""