feat: v7.0.0 — 6 new engineering skills, badges, milestone tracker, SKILL_REQUEST.md

New skills added to pm-engineering bundle (now 10 skills total):
- debugging-log-analyser: stack trace → structured root cause diagnosis + fix
- pr-description-writer: diff/commits → reviewer-ready PR description
- system-design-interview: full system design with capacity, components, trade-offs
- changelog-generator: git log → polished Keep a Changelog entry
- test-strategy-doc: spec/PRD → complete test strategy with P0/P1 test cases
- runbook-writer: operational runbooks with exact commands, rollback, and escalation

README updates:
- 5 shields.io badges (stars, skill count, version, install, license)
- "See It in Action" demo section
- pm-engineering added to Quick Install list
- Star Milestone Tracker (100/250/500/1000 stars roadmap)
- Engineering table extended from 4 to 10 skills (41–50)
- Article 14 link resolved from remote merge

Config updates:
- marketplace.json: v6.0.0 → v7.0.0, "106 skills"
- pm-engineering plugin.json: v1.0.0 → v2.0.0

New file: SKILL_REQUEST.md — community skill voting board

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/pm-engineering/skills/debugging-log-analyser/SKILL.md

@@ -0,0 +1,79 @@
+---
+name: debugging-log-analyser
+description: "Parse error logs, stack traces, and crash reports into a structured root cause diagnosis. Use when sharing a log, stack trace, error output, or crash dump. Produces a structured diagnosis with probable root cause, affected code path, suggested fix, and next debugging steps. Optimised for Opus 4.7 and newer models."
+---
+
+# Debugging Log Analyser Skill
+
+Parses raw error logs, stack traces, and crash reports into a structured diagnosis with probable root cause, affected code path, and specific next steps — no hand-waving.
+
+## Required Inputs
+
+Ask for these if not provided:
+- **The log / stack trace / error output** (paste directly or describe the error)
+- **Language and framework** (e.g. Node.js + Express, Python + Django, Java Spring, Go)
+- **Context** (what the user was doing when the error occurred)
+- **Environment** (local dev / staging / production)
+- **What they've already tried** (if anything)
+
+## Output Structure
+
+### 1. Error Classification
+**Error type:** [Runtime exception / Build error / Config error / Network error / Memory/resource error / Unknown]
+**Severity:** [Fatal / Critical / Warning / Informational]
+**Recurrence pattern:** [One-off / Intermittent / Consistent / On-startup / Under load]
+
+### 2. Stack Trace Analysis
+
+Walk the stack frame by frame, starting from the origin:
+- **Origin frame:** [File, line, function where it started]
+- **Propagation path:** [How it travelled through the call stack]
+- **Crash point:** [Where it ultimately threw/panicked/exited]
+
+For each significant frame, note whether it is:
+- User code (fixable here)
+- Framework/library code (usually a misuse issue)
+- System/runtime code (usually a config or environment issue)
+
+### 3. Root Cause Assessment
+**Probable root cause:** [1–2 sentence plain English statement]
+**Confidence:** [High / Medium / Low — and why]
+**Alternative causes to rule out:** [If confidence is not high]
+
+### 4. Affected Code Path
+**Entry point:** [Where the triggering call began]
+**Key function(s) involved:** [Specific functions/methods named in the trace]
+**Data that triggered it:** [If inferable from the log — e.g. null value, malformed JSON]
+
+### 5. Suggested Fix
+Provide a concrete, code-level suggestion:
+- What to change (the minimal fix)
+- Why this fixes the root cause
+- Any trade-offs or risks in the fix
+- A short code snippet if helpful
+
+### 6. Next Debugging Steps
+If the root cause is uncertain, provide an ordered list of 3–5 specific debugging actions:
+1. [Specific thing to check — file, log line, config value]
+2. [Specific reproduction step or isolation test]
+3. [Specific tool command — e.g. `strace`, `pprof`, `--verbose`, add logging at X]
+
+### 7. Prevention
+One or two concrete things that would prevent this class of error recurring:
+- Better input validation at [point]
+- Add monitoring/alerting for [condition]
+- Test that covers [scenario]
+
+## Quality Checks
+- [ ] Root cause is specific (not "there might be a null pointer issue")
+- [ ] At least one concrete code-level fix is suggested
+- [ ] Next steps are actionable commands, not vague advice
+- [ ] Language-specific idioms are used correctly
+- [ ] Prevention is proactive (not just "add error handling")
+
+## Example Trigger Phrases
+- "Why is this crashing?" + [paste log]
+- "Can you analyse this stack trace?"
+- "I'm getting this error, what does it mean?"
+- "Debug this log for me"
+- "What's causing this exception?"