fix(ce-learnings-researcher): drop unreadable schema path reference (#630)

plugins/compound-engineering/agents/ce-learnings-researcher.agent.md

@@ -163,14 +163,14 @@ Fill `**Problem Type**` with the raw `problem_type` value from the frontmatter (
 
 ## Frontmatter Schema Reference
 
-The authoritative schema lives at `../../skills/ce-compound/references/yaml-schema.md`; read it on demand when you need the full contract, including `component` and `root_cause` enums (those are repo-specific and evolve — do not hard-code them here).
-
-The two `problem_type` tracks worth knowing in advance:
+The two `problem_type` tracks:
 
 - **Knowledge-track:** `architecture_pattern`, `design_pattern`, `tooling_decision`, `convention`, `workflow_issue`, `developer_experience`, `documentation_gap`, `best_practice` (fallback).
 - **Bug-track:** `build_error`, `test_failure`, `runtime_error`, `performance_issue`, `database_issue`, `security_issue`, `ui_bug`, `integration_issue`, `logic_error`.
 
-Subdirectory listings in the schema reference are illustrative, not exhaustive. Probe the live directory (Step 2) for what actually exists.
+Other frontmatter fields (`component`, `root_cause`, etc.) are repo-specific and evolve over time. Do not assume a fixed enum — read the value from each file as-is, and when summarizing a learning with an unrecognized value, pass it through verbatim rather than normalizing it.
+
+Probe the live `docs/solutions/` directory (Step 2) for what actually exists; do not hard-code subdirectory names.
 
 ## Output Format