feat: SkillForge — automated skill discovery, evaluation & integration engine (#144)

* feat: add SkillForge — automated skill discovery, evaluation, and integration engine

SkillForge adds a 3-stage pipeline for autonomous skill management:

- Scout: discovers candidate skills from GitHub (extensible to ClawHub, HuggingFace)
- Evaluate: scores candidates on compatibility, quality, and security (weighted 0.30/0.35/0.35)
- Integrate: generates standard SKILL.toml + SKILL.md manifests for approved candidates

Thresholds: >=0.7 auto-integrate, 0.4-0.7 manual review, <0.4 skip.
Uses only existing dependencies (reqwest, serde, tokio, tracing, chrono, anyhow).
Includes unit tests for all modules.

* fix: address code review feedback on SkillForge PR #115

- evaluate: whole-word matching for BAD_PATTERNS (fixes hackathon false positive)
- evaluate: guard against future timestamps in recency bonus
- integrate: escape URLs in TOML output via escape_toml()
- integrate: handle control chars (\n, \r, \t, \b, \f) in escape_toml()
- mod: redact github_token in Debug impl to prevent log leakage
- mod: fix auto_integrated count when auto_integrate=false
- mod: per-candidate error handling (single failure no longer aborts pipeline)
- scout: add 30s request timeout, remove unused token field
- deps: enable chrono serde feature for DateTime serialization
- tests: add hackathon/exact-hack tests, update escape_toml test coverage

* fix: address round-2 CodeRabbit review feedback

- integrate: add sanitize_path_component() to prevent directory traversal
- mod: GitHub scout failure now logs warning and continues (no pipeline abort)
- scout: network/parse errors per-query use warn+continue instead of ?
- scout: implement std::str::FromStr for ScoutSource (replaces custom from_str)
- tests: add path sanitization tests (traversal, separators, dot trimming)

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Co-authored-by: stawky <stakeswky@gmail.com>

Cargo.lock

@@ -297,6 +297,7 @@ checksum = "fac4744fb15ae8337dc853fee7fb3f4e48c0fbaa23d0afe49c447b4fab126118"
 dependencies = [
  "iana-time-zone",
  "num-traits",
+ "serde",
  "windows-link",
 ]