fix(skills): fix CI gate failures blocking PR #1506 merge

Fix pre-existing lint, typecheck, and security failures that were
blocking the PR from passing CI:

- Fix E501 line-too-long in session_service.py (remove erroneous
  "sha256:" string prefix from dict comprehension on line 268)
- Fix W293 trailing whitespace in tool.py line 249
- Fix typecheck error in session_service.py: data.get("checksum")
  can return None, remove invalid string concatenation
- Fix typecheck error in schema.py: add explicit dict[str, Any]
  type annotation for wrapper variable to resolve str|None issue
- Fix vulture false positive: add "destination" Protocol parameter
  to vulture_whitelist.py
- Fix @tdd_issue/@tdd_issue_1472 tag placement in skill_schema.feature
  (remove blank line between tags and scenario)
- Add @tdd_issue/@tdd_issue_1472 tags to all new wrapper key scenarios
- Add Robot integration test for spec-compliant skill: wrapper YAML

features/skill_schema.feature

@@ -316,7 +316,6 @@ Feature: Skill YAML schema validation
   # ────────────────────────────────────────────────────────────
   @tdd_issue
   @tdd_issue_1472
-
   Scenario: Load spec-compliant YAML with skill: wrapper key
     Given a spec-compliant skill YAML with skill: wrapper key
     When I validate the skill schema
@@ -324,36 +323,48 @@ Feature: Skill YAML schema validation
     And the skill config name should be "local/wrapped-skill"
     And the skill config should have 1 tools
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: Load spec-compliant YAML with cleveragents: header and skill: wrapper
     Given a spec-compliant skill YAML with cleveragents: header and skill: wrapper
     When I validate the skill schema
     Then the skill schema validation should succeed
     And the skill config name should be "local/wrapped-with-meta"
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: skill: wrapper key with None value raises ValueError
     Given a skill YAML with skill: wrapper key with None value
     When I validate the skill schema expecting failure
     Then the skill schema validation should fail
     And the skill schema error should mention "empty"
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: skill: wrapper key with non-dict value raises ValueError
     Given a skill YAML with skill: wrapper key and string value
     When I validate the skill schema expecting failure
     Then the skill schema validation should fail
     And the skill schema error should mention "mapping"
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: skill: wrapper key with list value raises ValueError
     Given a skill YAML with skill: wrapper key and list value
     When I validate the skill schema expecting failure
     Then the skill schema validation should fail
     And the skill schema error should mention "mapping"
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: Flat YAML without wrapper key still works (backward compatibility)
     Given a skill YAML string with only the name field
     When I validate the skill schema
     Then the skill schema validation should succeed
     And the skill config name should be "local/empty-skill"
 
+  @tdd_issue
+  @tdd_issue_1472
   Scenario: cleveragents: header alone (flat format with metadata, no skill: wrapper)
     Given a skill YAML with cleveragents: header and flat format
     When I validate the skill schema

robot/skill_schema.robot

@@ -49,3 +49,15 @@ Reject Invalid Skill YAML
     Should Be Equal As Integers    ${result.rc}    0
     Should Contain    ${result.stdout}    skill-schema-expected-fail
 
+Validate Spec-Compliant Skill YAML With skill: Wrapper Key
+    [Tags]    tdd_issue    tdd_issue_1472
+    [Documentation]    Parse a spec-compliant YAML with cleveragents: header and skill: wrapper key
+    ${wrapped_yaml}=    Set Variable    ${TEMPDIR}${/}wrapped_skill.yaml
+    ${yaml_content}=    Set Variable    cleveragents:\n  version: "1.0"\nskill:\n  name: local/wrapped-skill\n  description: "A wrapped skill"\n
+    Create File    ${wrapped_yaml}    ${yaml_content}
+    ${result}=    Run Process    ${PYTHON}    ${HELPER}    validate    ${wrapped_yaml}    cwd=${WORKSPACE}
+    Log    ${result.stdout}
+    Log    ${result.stderr}
+    Should Be Equal As Integers    ${result.rc}    0
+    Should Contain    ${result.stdout}    skill-schema-ok
+

src/cleveragents/skills/schema.py

@@ -465,7 +465,8 @@ class SkillConfigSchema(BaseModel):
             # Merge wrapper content with normalized keys.
             # Wrapper values take precedence so the spec-compliant
             # format works reliably even if both formats overlap.
-            for key, value in wrapper.items():
+            wrapper_dict: dict[str, Any] = wrapper
+            for key, value in wrapper_dict.items():
                 snake_key = _CAMEL_TO_SNAKE.get(key, key)
                 normalized[snake_key] = value