feat(nacos): Update NacosSkillRepository extension module version (#1080)

### Description

**Background & motivation**  
Enable AgentScope-Java to load AI Skill packages from Nacos via
`AiService`, aligned with `AgentSkillRepository` and `AgentSkill`, so
teams using Nacos can host, version, or label skills in one place.

**What changed**

- New module **`agentscope-extensions-nacos-skill`**:
`NacosSkillRepository` implements `AgentSkillRepository`, downloads the
skill ZIP through Nacos `AiService` (`downloadSkillZip`,
`downloadSkillZipByVersion`, `downloadSkillZipByLabel`), then parses it
with `SkillUtil#createFromZip`.
- **Version & label resolution**: `agentscope.nacos.skill.version` /
`agentscope.nacos.skill.label` from `Properties`, JVM system properties,
or env vars (`AGENTSCOPE_NACOS_SKILL_VERSION` /
`AGENTSCOPE_NACOS_SKILL_LABEL`); precedence is documented on the class.
- **Read-only semantics**: `getSkill`, `skillExists`,
`getRepositoryInfo`, `getSource`, `isWriteable` are implemented;
list/write APIs (`getAllSkillNames`, `getAllSkills`, `save`, `delete`)
are documented no-ops with warnings.
- **YAML frontmatter adaptation**: Rewrites Nacos-exported `SKILL.md`
frontmatter (indented continuation lines) so it matches AgentScope’s
flat `key: value` parsing.
- **Build & distribution**: Module is wired under
`agentscope-extensions-nacos`, and included in `agentscope-bom` /
`agentscope-all` for dependency alignment; `nacos-client` version is
managed in the BOM.

**How to test**

1. Format: `mvn spotless:apply` (whole repo or selected modules).
2. Unit tests: `mvn test -pl
agentscope-extensions/agentscope-extensions-nacos/agentscope-extensions-nacos-skill`.
3. Optional integration: Use a real Nacos AI skill and `AiService`,
build `NacosSkillRepository(aiService, namespaceId, properties)`, call
`getSkill` / `skillExists`; repeat with version or label properties set.

Author: qiacheng7

agentscope-dependencies-bom/pom.xml

@@ -104,7 +104,7 @@
         <quartz.version>2.5.2</quartz.version>
         <spring.version>7.0.6</spring.version>
         <spring-boot.version>4.0.4</spring-boot.version>
-        <nacos-client.version>3.2.0-BETA</nacos-client.version>
+        <nacos-client.version>3.2.1-2026.03.30</nacos-client.version>
         <json-schema-validator.version>3.0.1</json-schema-validator.version>
         <jsonschema-generator.version>4.38.0</jsonschema-generator.version>
         <snakeyaml.version>2.6</snakeyaml.version>