refactor(cli): change from env var injection to direct prompt concatenation

- Replace $PROTO/$TMPL environment variable injection with systemRules/roles direct concatenation
- Append rules to END of prompt instead of prepending
- Change prompt field name from RULES to CONSTRAINTS in all prompts
- Default to universal-rigorous-style template when --rule not specified
- Update all .claude documentation, agents, commands, and skills
- Add streaming_content type support for Gemini delta messages

Breaking: Prompts now use CONSTRAINTS field instead of RULES

.claude/workflows/cli-templates/prompts/workflow-skill-conflict-patterns.txt

@@ -76,7 +76,7 @@ TASK: • Extract conflicts from IMPL_PLAN and lessons • Group by type (archit
 MODE: analysis
 CONTEXT: @.workflow/.archives/*/IMPL_PLAN.md @.workflow/.archives/manifest.json
 EXPECTED: Conflict patterns with frequency and resolution
-RULES: $PROTO $TMPL | analysis=READ-ONLY
+CONSTRAINTS: analysis=READ-ONLY
 " --tool gemini --mode analysis --rule workflow-skill-aggregation --cd .workflow/.archives
 ```
 

.claude/workflows/cli-templates/prompts/workflow-skill-lessons-learned.txt

@@ -72,7 +72,7 @@ TASK: • Group successes by functional domain • Categorize challenges by seve
 MODE: analysis
 CONTEXT: @.workflow/.archives/manifest.json
 EXPECTED: Aggregated lessons with frequency counts
-RULES: $PROTO $TMPL | analysis=READ-ONLY
+CONSTRAINTS: analysis=READ-ONLY
 " --tool gemini --mode analysis --rule workflow-skill-aggregation --cd .workflow/.archives
 ```