docs: full-page sentence-case sweep across 6 pages

- platforms/oracle: Cost Comparison (2026), Still Recommended, Verify Security Posture
- install/exe-dev: Automated Install with Shelley, Remote Access
- platforms/mac/dev-setup: Build Fails: Toolchain or SDK Mismatch, App Crashes on Permission Grant
- reference/AGENTS.default: What OpenClaw Does, Core Skills, Usage Notes
- install/docker: Containerized Gateway, Agent Sandbox
- ci: Package Acceptance, Job Overview, Local Equivalents

docs/reference/AGENTS.default.md

@@ -89,13 +89,13 @@ git commit -m "Add Clawd workspace"
 # Optional: add a private remote + push
 ```
 
-## What OpenClaw Does
+## What OpenClaw does
 
 - Runs WhatsApp gateway + Pi coding agent so the assistant can read/write chats, fetch context, and run skills via the host Mac.
 - macOS app manages permissions (screen recording, notifications, microphone) and exposes the `openclaw` CLI via its bundled binary.
 - Direct chats collapse into the agent's `main` session by default; groups stay isolated as `agent:<agentId>:<channel>:group:<id>` (rooms/channels: `agent:<agentId>:<channel>:channel:<id>`); heartbeats keep background tasks alive.
 
-## Core Skills (enable in Settings → Skills)
+## Core skills (enable in Settings → Skills)
 
 - **mcporter** — Tool server runtime/CLI for managing external skill backends.
 - **Peekaboo** — Fast macOS screenshots with optional AI vision analysis.
@@ -115,7 +115,7 @@ git commit -m "Add Clawd workspace"
 - **Gemini CLI** — Google Gemini models from the terminal for fast Q&A.
 - **agent-tools** — Utility toolkit for automations and helper scripts.
 
-## Usage Notes
+## Usage notes
 
 - Prefer the `openclaw` CLI for scripting; mac app handles permissions.
 - Run installs from the Skills tab; it hides the button if a binary is already present.