fix(docs): deduplicate titles across 9 pages

Differentiate titles that were identical across multiple pages:
- Platform pages: add '(Platform)' suffix to distinguish from install guides
- Legacy root-level pages: add '(legacy path)' suffix for files that
  redirect to canonical tools/ paths
- Logging: 'Logging' -> 'Logging Overview' (root) and 'Gateway Logging'
- building-extensions: add '(redirect)' suffix

docs/brave-search.md

@@ -3,7 +3,7 @@ summary: "Brave Search API setup for web_search"
 read_when:
   - You want to use Brave Search for web_search
   - You need a BRAVE_API_KEY or plan details
-title: "Brave Search"
+title: "Brave Search (legacy path)"
 ---
 
 # Brave Search API

docs/gateway/logging.md

@@ -3,7 +3,7 @@ summary: "Logging surfaces, file logs, WS log styles, and console formatting"
 read_when:
   - Changing logging output or formats
   - Debugging CLI or gateway output
-title: "Logging"
+title: "Gateway Logging"
 ---
 
 # Logging

docs/logging.md

@@ -4,7 +4,7 @@ read_when:
   - You need a beginner-friendly overview of logging
   - You want to configure log levels or formats
   - You are troubleshooting and need to find logs quickly
-title: "Logging"
+title: "Logging Overview"
 ---
 
 # Logging

docs/perplexity.md

@@ -3,7 +3,7 @@ summary: "Perplexity Search API and Sonar/OpenRouter compatibility for web_searc
 read_when:
   - You want to use Perplexity Search for web search
   - You need PERPLEXITY_API_KEY or OPENROUTER_API_KEY setup
-title: "Perplexity Search"
+title: "Perplexity Search (legacy path)"
 ---
 
 # Perplexity Search API

docs/platforms/digitalocean.md

@@ -3,7 +3,7 @@ summary: "OpenClaw on DigitalOcean (simple paid VPS option)"
 read_when:
   - Setting up OpenClaw on DigitalOcean
   - Looking for cheap VPS hosting for OpenClaw
-title: "DigitalOcean"
+title: "DigitalOcean (Platform)"
 ---
 
 # OpenClaw on DigitalOcean

docs/platforms/oracle.md

@@ -4,7 +4,7 @@ read_when:
   - Setting up OpenClaw on Oracle Cloud
   - Looking for low-cost VPS hosting for OpenClaw
   - Want 24/7 OpenClaw on a small server
-title: "Oracle Cloud"
+title: "Oracle Cloud (Platform)"
 ---
 
 # OpenClaw on Oracle Cloud (OCI)

docs/platforms/raspberry-pi.md

@@ -4,7 +4,7 @@ read_when:
   - Setting up OpenClaw on a Raspberry Pi
   - Running OpenClaw on ARM devices
   - Building a cheap always-on personal AI
-title: "Raspberry Pi"
+title: "Raspberry Pi (Platform)"
 ---
 
 # OpenClaw on Raspberry Pi

docs/plugins/building-extensions.md

@@ -1,5 +1,5 @@
 ---
-title: "Building Plugins"
+title: "Building Plugins (redirect)"
 summary: "Redirects to the current Building Plugins guide"
 read_when:
   - Legacy link to building-extensions

docs/tts.md

@@ -4,7 +4,7 @@ read_when:
   - Enabling text-to-speech for replies
   - Configuring TTS providers or limits
   - Using /tts commands
-title: "Text-to-Speech"
+title: "Text-to-Speech (legacy path)"
 ---
 
 # Text-to-speech (TTS)