Fix build.sh: remove non-existent tools (capabilities, notifications, tasks, talk)

Only build tools that actually exist:
- nextcloud-client (WebDAV files)
- nextcloud-contacts (CardDAV address books)
- nextcloud-calendar (CalDAV events)
- nextcloud-mail (IMAP/SMTP email)

Updated README to reflect correct tool count

README.md

@@ -24,7 +24,7 @@ All three skills now include an automatic bootstrap process:
 - ✅ No need to manually find/create app tokens
 - ✅ User experience is simpler (just username + password)
 - ✅ All credentials are forgotten immediately (security)
-- ✅ All three tools built together with same token
+- ✅ All tools built together with same token
 
 **Security:**
 - Username and password only used during authentication (temporary)
@@ -38,7 +38,7 @@ All three skills now include an automatic bootstrap process:
 
 ### Bootstrap Process (Automatic)
 
-All three Nextcloud SKILL.md files now include a secure bootstrap process:
+All Nextcloud SKILL.md files now include a secure bootstrap process:
 
 **The skill will:**
 1. Ask for your normal Nextcloud credentials (username and password)
@@ -60,7 +60,7 @@ User: "Hey, use the Nextcloud skill"
 Skill: "I'll set up your Nextcloud tools. What's your Nextcloud username and password?"
 User: "wltbagent@shortcutsolutions.net" and "mypassword"
 Skill: [Authenticates to Nextcloud, retrieves token, builds tools, forgets credentials]
-Skill: "All done! Now you can use: nextcloud-list, nextcloud-list-books, nextcloud-list-calendars"
+Skill: "All done! Now you can use: nextcloud-client, nextcloud-contacts, nextcloud-calendar"
 ```
 
 **Security:**
@@ -271,7 +271,7 @@ Use the provided build script:
 ```
 
 **The build script will:**
-1. Build Nextcloud API tools (Files, Contacts, Calendar, etc.) with the provided credentials
+1. Build Nextcloud API tools (Files, Contacts, Calendar) with the provided credentials
 2. **Prompt you for separate IMAP/SMTP credentials** for the email integration
 3. Build nextcloud-mail with email-specific credentials
 4. Install all binaries to `~/bin/`