fix: skills & memory — tool-name encoding, schema normalization, warm-cache, combo id, Ponytail catalog (#9058)

* feat(skills): add Ponytail minimalism skill as external catalog entry

- Add 'external' SkillCategory + SkillArea
- Register ponytail (MIT, DietrichGebert/ponytail) in CURATED_SKILLS
- Generator: external skills carry content in custom block, no api/cli body
- Generate skills/ponytail/SKILL.md with original content preserved
- Update catalog test counts 45 -> 46

* fix(skills+memory): builtin handler fallback in executor, skip vector upsert for deleted memories

- skills: Next.js compiles SkillExecutor into multiple chunks (own singleton
  each); route chunk lacked builtin handlers registered at startup via
  instrumentation. execute() now falls back to builtinSkills registry, so
  POST /api/skills/executions works for file_read/web_fetch/etc.
- memory: scheduleVectorUpsert is fire-and-forget and embeddings are slow;
  health-check verify (create->delete test memory) left queued upserts
  failing with 'memory not found' every 30s. Check existence before embedding
  and skip quietly.

* fix(skills): encode tool names with @ and . for providers rejecting them

Skill tools were advertised as 'name@version' (e.g. test-fr2@1.0.0), but
DeepSeek/Groq/OpenAI reject function names not matching ^[a-zA-Z0-9_-]+$.
Names already valid are left untouched; invalid ones are reversibly encoded
as omr_skill_<base64url> and decoded in interception before registry lookup.

* fix(combos): include DB id column in combo records for dashboard links

getCombos() selected only data/sort_order/context_cache_protection, so
combos whose JSON blob lacked an id field returned id: undefined. The
dashboard then linked to /dashboard/combos/undefined and Combo Control
Center failed with 'Combo not found'. Merge the id column into parsed
rows (authoritative, only when the blob has no id).

* fix(skills): normalize flat skill schemas to object schema for Gemini/Claude

Stored skill schemas are flat property maps ({ text: { type: string } }),
which OpenAI-compatible providers tolerate but Gemini
(function_declarations[].parameters) rejects with 'Unknown name ... Cannot
find field'. Wrap bare maps into { type: 'object', properties: {...} } for
all three tool formats.

* fix(skills): warm registry cache before skill injection in chat path

injectSkills() lists the in-memory skillRegistry, which is empty after a
cold start until something calls loadFromDatabase(). The interception path
already warms the cache (#2815); the injection path did not, so skills
were silently skipped (no_enabled_skills) for the first requests after
restart. Warm the cache for the chat owner before injection.

---------

Co-authored-by: Egor <egorich-print@users.noreply.github.com>

src/shared/constants/agentSkills.ts

@@ -463,4 +463,17 @@ export const CURATED_SKILLS: CuratedSkillEntry[] = [
     icon: "explore",
     isNew: true,
   },
+
+  // ── External (third-party) Skills ─────────────────────────────────────────
+
+  {
+    id: "ponytail",
+    name: "Ponytail (Minimalism Ladder)",
+    description:
+      "External agent skill (MIT, github.com/DietrichGebert/ponytail). Forces the laziest solution that actually works: question whether the task needs to exist at all (YAGNI), reuse what is already in the codebase, reach for the standard library before custom code, native platform features before dependencies, one line before fifty. Climb the ladder on every coding task — writing, adding, refactoring, fixing, reviewing, or designing code, and choosing libraries or dependencies. Supports intensity levels: lite, full (default), ultra. Never cut validation, error handling, security, or accessibility.",
+    category: "external",
+    area: "external",
+    icon: "compress",
+    isNew: true,
+  },
 ];