docs: apply documentation review fixes (§1–§5)

[brickbots]

Applies sections 1–5 of the June 2026 documentation review (navigation, bugs, contradictions, terminology, de-duplication). Built clean with sphinx-build -n — zero warnings.

§1 Navigation

• Sidebar split into three captioned groups: Using your PiFinder / Building & upgrading / For developers; unused :glob: removed.

§2 Bugs

• index.rst Markdown-syntax link replaced with proper :doc: links.
• dev_guide.rst unparsed code-block (missing blank line) and stray-space blockquote fixed.
• Stale v1 key names corrected against the code: screenshots are hold SQUARE + 0 (keyboard_pi.py), debug mode toggles via Tools › Console then 0 (ui/console.py).
• "Global Options" → Status screen; typo fixes in software.rst and dev_guide.rst.

§3 Contradictions (per the agreed resolution table)

• BOM: external power 2A minimum (1.5A noted as startup peak), runtime arithmetic aligned with the user guide, gerbers link → release.
• Minimum software version single-sourced as an rst_epilog substitution (|min_software| = 2.2.0) and applied on all five pages.
• Build guide scope note: DIY v2.5 build in Left/Right/Flat; v3 sold assembled.
• Custom RA/Dec targets documented (new user-guide section with fresh screenshots; flow verified against the running app), Objects menu updated to five options, stale Objects/Tools menu screenshots re-captured.
• User guide Tools section now defers to the Menu Map instead of enumerating a stale list.

§4 Terminology

• Quick Menu everywhere (was "Radial Menu" ×4 and one "marking menu"); one-time "(the radial menu)" bridge kept at first Quick Start mention.
• Accelerometer ↔ IMU vocabularies tied with a single parenthetical in How It Works.

§5 De-duplication

• Shutdown steps: full procedure lives in the user guide; Quick Start reduced to the gesture + link.
• Standalone user-guide Brightness section deleted; one sentence folded into Battery life.
• SkySafari connection parameters live only on the SkySafari page.
• Camera Prep / cable-connect steps shared between build and upgrade guides via .. include:: snippets (docs/source/includes/).
• Quick Start "can't solve?" note trimmed to the two likely causes + troubleshooting link; user-guide FAQ stub removed.
• Menu-basics lists in Quick Start/User Guide flagged as a linked pair with RST comments.

Also fixes two pre-existing build warnings: the inconsistent heading ladder in build_guide.rst (10 Title level inconsistent CRITICALs) and the dead _static path in conf.py.

🤖 Generated with Claude Code