fix: Enhance Kol Variable Rendering and Management

- Updated the regex for placeholder matching to support more flexible key formats.
- Refactored variable storage to allow both ID and key lookups in rendering.
- Improved schema validation to check for duplicate keys and enforce non-empty keys.
- Added new utility functions for variable value lookup and display name generation.
- Enhanced tests to cover new key-based variable scenarios.
- Refactored KolPrompt repository to simplify prompt storage and management, including the removal of obsolete revision handling.
- Introduced new API endpoints for saving, activating, and archiving prompts.
- Added new utility functions for handling Kol placeholders and platform options in the admin web.
- Implemented database migrations to simplify prompt storage structure and ensure data integrity.

server/migrations/20260418110000_simplify_kol_prompt_storage.down.sql

@@ -0,0 +1,12 @@
+ALTER TABLE kol_usage_logs
+    DROP CONSTRAINT IF EXISTS fk_kol_usage_logs_prompt_revision;
+
+ALTER TABLE kol_usage_logs
+    ADD CONSTRAINT fk_kol_usage_logs_prompt_revision
+    FOREIGN KEY (prompt_id, prompt_revision_no)
+    REFERENCES kol_prompt_revisions(prompt_id, revision_no);
+
+ALTER TABLE kol_prompts
+    DROP COLUMN IF EXISTS card_config_json,
+    DROP COLUMN IF EXISTS schema_json,
+    DROP COLUMN IF EXISTS prompt_asset_key;

server/migrations/20260418110000_simplify_kol_prompt_storage.up.sql

@@ -0,0 +1,37 @@
+ALTER TABLE kol_prompts
+    ADD COLUMN IF NOT EXISTS prompt_asset_key TEXT,
+    ADD COLUMN IF NOT EXISTS schema_json JSONB NOT NULL DEFAULT '{}'::jsonb,
+    ADD COLUMN IF NOT EXISTS card_config_json JSONB NOT NULL DEFAULT '{}'::jsonb;
+
+WITH preferred_revisions AS (
+    SELECT DISTINCT ON (p.id)
+           p.id AS prompt_id,
+           pr.prompt_asset_key,
+           pr.schema_json,
+           pr.card_config_json
+    FROM kol_prompts p
+    JOIN kol_prompt_revisions pr ON pr.prompt_id = p.id
+    ORDER BY p.id,
+             CASE
+                 WHEN p.published_revision_no IS NOT NULL AND pr.revision_no = p.published_revision_no THEN 0
+                 WHEN p.draft_revision_no IS NOT NULL AND pr.revision_no = p.draft_revision_no THEN 1
+                 ELSE 2
+             END,
+             pr.revision_no DESC
+)
+UPDATE kol_prompts p
+SET prompt_asset_key = r.prompt_asset_key,
+    schema_json = COALESCE(r.schema_json, '{}'::jsonb),
+    card_config_json = COALESCE(r.card_config_json, '{}'::jsonb)
+FROM preferred_revisions r
+WHERE p.id = r.prompt_id
+  AND (p.prompt_asset_key IS NULL OR btrim(p.prompt_asset_key) = '');
+
+UPDATE kol_prompts
+SET published_revision_no = 1,
+    draft_revision_no = NULL
+WHERE prompt_asset_key IS NOT NULL
+  AND btrim(prompt_asset_key) <> '';
+
+ALTER TABLE kol_usage_logs
+    DROP CONSTRAINT IF EXISTS fk_kol_usage_logs_prompt_revision;