feat: add sdk-feature, sdk-parity, sdk-review skills

[OMpawar-21]

Summary

Adds three management SDK automation skills to support feature parity across the Contentstack management SDK portfolio (JS, Python, Java, .NET).

Skills Added

sdk-feature — Full 11-step implementation pipeline:

• CMA OpenAPI spec as primary source of truth
• TDD-first: all tests written before implementation
• 12-check architecture scan (naming, HTTP pattern, reuse check, deprecated, docstrings)
• Security gates: Talisman → Snyk → TruffleHog
• Human manual review gate with per-SDK approval
• Model separation: higher model for thinking/design/review, lower for code writing
• Multi-SDK agent strategy: isolated context per SDK, independent error recovery

sdk-parity — Parity audit across all management SDKs:

• Fetches CMA OpenAPI spec dynamically — no hardcoded resource list
• Endpoint-based matching (catches aliases like query↔find, import↔imports)
• Dynamic file discovery via grep — no hardcoded paths
• Generates HTML parity report

sdk-review — Independent 3-pass code review:

• Pass 1: 10 checks (spec, plan, return types, param naming, docstrings, deprecated, cross-SDK method count)
• Pass 2: test quality (meaningful assertions, negative paths, cross-SDK parity)
• Pass 3: full regression suite

Context

Built as part of DevEx workspace SDK automation initiative (DX-10180).
Short-term: skills live in sdk-automation/ in devex-workspace, synced via make generate.
Long-term: this repo is the canonical home.

Test Plan

• Install skill: npx skills add contentstack/contentstack-agent-skills --skill sdk-feature
• /sdk-feature in Claude Code — verify pipeline steps appear
• /sdk-parity in Claude Code — verify gap table output
• /sdk-review repos/contentstack-management-python — verify 3-pass review

🤖 Generated with Claude Code

[github-actions]

🔒 Security Scan Results

ℹ️ Note: Only vulnerabilities with available fixes (upgrades or patches) are counted toward thresholds.

Check Type	Count (with fixes)	Without fixes	Threshold	Result
🔴 Critical Severity	0	0	10	✅ Passed
🟠 High Severity	0	0	25	✅ Passed
🟡 Medium Severity	0	0	500	✅ Passed
🔵 Low Severity	0	0	1000	✅ Passed

⏱️ SLA Breach Summary

✅ No SLA breaches detected. All vulnerabilities are within acceptable time thresholds.

Severity	Breaches (with fixes)	Breaches (no fixes)	SLA Threshold (with/no fixes)	Status
🔴 Critical	0	0	15 / 30 days	✅ Passed
🟠 High	0	0	30 / 120 days	✅ Passed
🟡 Medium	0	0	90 / 365 days	✅ Passed
🔵 Low	0	0	180 / 365 days	✅ Passed

✅ BUILD PASSED - All security checks passed