docs: full-page readability pass on 5 worst-offender pages

- automation/standing-orders: sentence-case all H2/H3 headings (Why Standing Orders, Anatomy, Execute-Verify-Report Pattern, Multi-Program Architecture, Best Practices, etc.) and clean up Related link styling
- platforms/raspberry-pi: sentence-case 10 headings (Hardware Requirements, Performance Optimizations, Cost Comparison, etc.)
- install/fly: sentence-case troubleshooting and Private Deployment headings
- pi-dev: drop 'this guide summarizes' filler, sentence-case 4 H2 headings, restore brand-cased Pi
- concepts/model-providers: sentence-case Kimi Coding (other brand-named providers preserved as-is: Google Gemini, Google Vertex, Kilo Gateway, Volcano Engine)

docs/pi-dev.md

@@ -6,15 +6,15 @@ read_when:
   - Running Pi-specific lint, typecheck, and live test flows
 ---
 
-This guide summarizes a sane workflow for working on the pi integration in OpenClaw.
+A sane workflow for working on the Pi integration in OpenClaw.
 
-## Type Checking and Linting
+## Type checking and linting
 
 - Default local gate: `pnpm check`
 - Build gate: `pnpm build` when the change can affect build output, packaging, or lazy-loading/module boundaries
 - Full landing gate for Pi-heavy changes: `pnpm check && pnpm test`
 
-## Running Pi Tests
+## Running Pi tests
 
 Run the Pi-focused test set directly with Vitest:
 
@@ -43,7 +43,7 @@ This covers the main Pi unit suites:
 - `src/agents/pi-tool-definition-adapter.test.ts`
 - `src/agents/pi-hooks/*.test.ts`
 
-## Manual Testing
+## Manual testing
 
 Recommended flow:
 
@@ -56,7 +56,7 @@ Recommended flow:
 
 For tool call behavior, prompt for a `read` or `exec` action so you can see tool streaming and payload handling.
 
-## Clean Slate Reset
+## Clean slate reset
 
 State lives under the OpenClaw state directory. Default is `~/.openclaw`. If `OPENCLAW_STATE_DIR` is set, use that directory instead.