refactor: flip cameleer-common consumer from com.cameleer to io.cameleer

The agent team finished their groupId+package migration; this commit
flips the corresponding consumer side here. Closes the dichotomy noted
in the prior "Registry naming" doc — io.cameleer is now uniform across
all three repos (server, agent, saas).

- 46 .java files: import com.cameleer.common.* → io.cameleer.common.*
- pom.xml + cameleer-server-core/pom.xml: cameleer-common dep groupId
- CLAUDE.md: drop the obsolete "stays on com.cameleer until institutionalized"
  qualifier on Related Project; flip Key Conventions dep coordinate
- cameleer-license-minter/README.md: GAV strings + main-class FQN

Verification: full reactor mvn test -DskipITs — 416 unit tests pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cameleer-server-core/pom.xml

@@ -20,7 +20,7 @@
             <artifactId>cameleer-license-api</artifactId>
         </dependency>
         <dependency>
-            <groupId>com.cameleer</groupId>
+            <groupId>io.cameleer</groupId>
             <artifactId>cameleer-common</artifactId>
         </dependency>
         <dependency>