refactor: Major v6 epic creation improvements and documentation overhaul

## Key Changes

### 1. Epic Creation Workflow Enhancements
- Added user-value focused epic structure principles (NO technical layer breakdown)
- Implemented multi-mode detection: CONTINUE, REPLACE, or UPDATE existing epics
- Added comprehensive anti-pattern examples showing wrong vs right epic breakdown
- Epics now created AFTER architecture for technically-informed story breakdown
- Added checkpoint protocol for interactive workflow progression

### 2. Removed Deprecated Solutioning Gate Check
- Deleted entire solutioning-gate-check workflow (682 lines)
- Replaced by new implementation-readiness workflow
- Cleaner separation of concerns in solutioning phase

### 3. PRD Template Simplification
- Removed hardcoded "Implementation Planning", "References", and "Next Steps" sections
- PRD now focuses purely on requirements, not workflow orchestration
- Epics/stories created as separate step after architecture

### 4. Documentation Overhaul (15+ docs updated)
- Updated quick-start guide with v6 workflow sequence
- Clarified that epics are created AFTER architecture, not during PRD
- Updated solutioning docs to reflect implementation-readiness pattern
- Improved agents-guide, brownfield-guide, enterprise docs
- Enhanced glossary, FAQ, and workflow reference documentation

### 5. Workflow Path Adjustments
- All 4 paths updated (enterprise/method × brownfield/greenfield)
- Version bumps across BMGD, BMM, and CIS workflow YAMLs
- Minor instruction file updates for consistency

### Files Changed
- 65 files total: 468 insertions, 978 deletions (net reduction of 510 lines)
- 4 files deleted (entire solutioning-gate-check workflow)
- 1 new directory added (implementation-readiness placeholder)

src/modules/bmm/workflows/workflow-status/paths/enterprise-brownfield.yaml

@@ -121,10 +121,10 @@ phases:
         command: "create-epics-and-stories"
         note: "Required: Create final epic breakdown with full context (PRD + UX + Architecture)"
 
-      - id: "solutioning-gate-check"
+      - id: "implementation-readiness"
         required: true
         agent: "architect"
-        command: "solutioning-gate-check"
+        command: "implementation-readiness"
         note: "Critical gate - validates all planning + Epics before touching production system"
 
   - phase: 3

src/modules/bmm/workflows/workflow-status/paths/enterprise-greenfield.yaml

@@ -109,10 +109,10 @@ phases:
         command: "create-epics-and-stories"
         note: "Required: Create final epic breakdown with full context (PRD + UX + Architecture)"
 
-      - id: "solutioning-gate-check"
+      - id: "implementation-readiness"
         required: true
         agent: "architect"
-        command: "solutioning-gate-check"
+        command: "implementation-readiness"
         note: "Validates all planning artifacts + Epics + testability align before implementation"
 
   - phase: 3

src/modules/bmm/workflows/workflow-status/paths/method-brownfield.yaml

@@ -105,11 +105,11 @@ phases:
         agent: "architect"
         command: "validate-architecture"
 
-      - id: "solutioning-gate-check"
+      - id: "implementation-readiness"
         required: true
         agent: "architect"
-        command: "solutioning-gate-check"
-        note: "Validates PRD + UX + Architecture + Epics (if created) cohesion"
+        command: "implementation-readiness"
+        note: "Validates PRD + UX + Architecture + Epics cohesion before implementation"
 
   - phase: 3
     name: "Implementation"

src/modules/bmm/workflows/workflow-status/paths/method-greenfield.yaml

@@ -96,10 +96,10 @@ phases:
         command: "validate-architecture"
         note: "Quality check for architecture completeness"
 
-      - id: "solutioning-gate-check"
+      - id: "implementation-readiness"
         required: true
         agent: "architect"
-        command: "solutioning-gate-check"
+        command: "implementation-readiness"
         note: "Validates PRD + UX + Architecture + Epics + Testability cohesion before implementation"
 
   - phase: 3