feat: implement agent-os standards system and feature planning tools

- Split CODING_GUIDELINES.md into 19 indexed standards files under .claude/standards/
  - 9 from CODING_GUIDELINES (conventions, powershell, security, api, git, gururmm)
  - 10 from session log tribal knowledge (syncro, ssh, gitea, python, client, gururmm)
- Add .claude/standards/index.yml for cheap relevance-based lookup
- Add /inject-standards command: load targeted standards per task instead of full guidelines
- Add /shape-spec command: pre-implementation spec for GuruRMM features (plan.md,
  shape.md, references.md, standards.md) with mandatory out-of-scope gate
- Add docs/tech-stack.md and docs/mission.md for ClaudeTools API
- Add projects/msp-tools/guru-rmm/docs/tech-stack.md and mission.md for GuruRMM
- Update CLAUDE.md commands table with /inject-standards and /shape-spec

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

.claude/standards/conventions/output-markers.md

@@ -0,0 +1,49 @@
+---
+name: output-markers
+description: ASCII status markers [OK] [ERROR] [WARNING] [SUCCESS] [INFO] [CRITICAL] for all scripts and tools
+applies-to: all
+---
+
+# Output Markers
+
+All scripts and tools use ASCII status markers instead of emoji, colored text, or ambiguous symbols.
+
+## Standard set
+
+```
+[INFO]     — informational, no action required
+[SUCCESS]  — operation completed successfully
+[WARNING]  — something is off but not fatal; attention recommended
+[ERROR]    — operation failed; action required
+[CRITICAL] — severe failure; immediate attention required
+[OK]       — shorter form of [SUCCESS], used in status tables and inline checks
+[GAP]      — used in parity matrices; feature not implemented on this platform
+[WARN]     — shorter form of [WARNING], used in parity matrices and inline checks
+```
+
+## Usage examples
+
+```bash
+echo "[INFO] Starting process"
+echo "[SUCCESS] Task completed"
+echo "[WARNING] Configuration file missing, using defaults"
+echo "[ERROR] Failed to connect to 172.16.3.30:3001"
+echo "[CRITICAL] Database unavailable — all writes are failing"
+```
+
+## In tables and parity matrices
+
+| Feature | Windows | Linux | macOS |
+|---------|---------|-------|-------|
+| CPU metrics | [OK] | [OK] | [OK] |
+| Temperature | [OK] primary | [WARN] partial | [WARN] partial |
+| Idle time | [OK] | [GAP] | [GAP] |
+
+## Applies to
+
+- Bash scripts
+- Python scripts and log messages
+- PowerShell scripts
+- Session log entries
+- Commit messages (use plain text, not markers, but no emoji)
+- Any output that may appear in a terminal or log file