refactor(bmad-customize): tighten description and expand module-help entry

- SKILL.md description: drop the catch-all 'or asks how to change the
  behavior of a specific BMad skill' trigger clause that would fire in
  casual discussion; keep the four explicit phrase triggers.
- module-help.csv: rewrite the description so bmad-help has real
  routing material — names the concrete capabilities (persistent
  facts, template swaps, activation hooks, menus), the scope routing,
  and the value prop (no TOML hand-authoring). Matches the 'Use
  when...' pattern other Core entries use.

src/core-skills/bmad-customize/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: bmad-customize
-description: Help users author or update project level custom overrides for customizable skills. Use when the user says 'customize bmad', 'override a skill', 'change agent behavior', 'customize a workflow', or asks how to change the behavior of a specific BMad skill.
+description: Authors and updates customization overrides for installed BMad skills. Use when the user says 'customize bmad', 'override a skill', 'change agent behavior', or 'customize a workflow'.
 ---
 
 # BMad Customize

src/core-skills/module-help.csv

@@ -10,4 +10,4 @@ Core,bmad-editorial-review-structure,Editorial Review - Structure,ES,Use when do
 Core,bmad-review-adversarial-general,Adversarial Review,AR,"Use for quality assurance or before finalizing deliverables. Code Review in other modules runs this automatically, but also useful for document reviews.",[path],anytime,,,false,,
 Core,bmad-review-edge-case-hunter,Edge Case Hunter Review,ECH,Use alongside adversarial review for orthogonal coverage — method-driven not attitude-driven.,[path],anytime,,,false,,
 Core,bmad-distillator,Distillator,DG,Use when you need token-efficient distillates that preserve all information for downstream LLM consumption.,[path],anytime,,,false,adjacent to source document or specified output_path,distillate markdown file(s)
-Core,bmad-customize,BMad Customize,BC,Use to author or update _bmad/custom TOML overrides for customizable agents and workflows.,,anytime,,,false,{project-root}/_bmad/custom,TOML override files
+Core,bmad-customize,BMad Customize,BC,Use when you want to change how an agent or workflow behaves — add persistent facts, swap templates, insert activation hooks, or customize menus. Scans what's customizable, picks the right scope (agent vs workflow), writes the override to _bmad/custom/, and verifies the merge. No TOML hand-authoring required.,,anytime,,,false,{project-root}/_bmad/custom,TOML override files