feat: Add YAML frontmatter metadata to all 132 skills

Add structured metadata to every skill file for improved discoverability:

**Metadata Added**:
- name: Unique identifier for each skill
- description: One-line summary of when to use the skill
- scope: Key topics covered (for some skills)
- lines: Approximate line count (for some skills)
- last_updated: Date of last significant update (for some skills)

**Benefits**:
- Better tooling integration (IDE plugins, search tools)
- Structured discovery via skill name/description
- Consistent metadata format across all 132 skills
- Enables future automation (skill indexing, cross-referencing)

**Coverage**:
- Core skills (66): API, Testing, Containers, Frontend, Database, Beads, iOS/Swift, Modal, Networking, TUI, Zig
- Advanced skills (25): CI/CD, Infrastructure, Observability, Real-time, Data Pipeline
- Specialized skills (41): Formal methods, ML/AI, Deployment, Math, Mobile

All skill files maintain backward compatibility - content unchanged, only frontmatter added.

Author: rand

skills/apache-iceberg.md

@@ -1,3 +1,10 @@
+---
+name: apache-iceberg
+description: Building data lakes with ACID transaction support and schema evolution
+---
+
+
+
 # Apache Iceberg
 
 **Scope**: Table format, schema/partition evolution, time travel, ACID transactions, catalog integration, performance optimization

skills/api/api-authentication.md

@@ -1,3 +1,10 @@
+---
+name: api-api-authentication
+description: Implementing API authentication for new services
+---
+
+
+
 # API Authentication
 
 **Scope**: Authentication strategies, JWT, OAuth 2.0, API keys, token management

skills/api/api-authorization.md

@@ -1,3 +1,10 @@
+---
+name: api-api-authorization
+description: Implementing authorization logic in APIs
+---
+
+
+
 # API Authorization
 
 **Scope**: Authorization models, permission systems, role-based access control

skills/api/api-error-handling.md

@@ -1,3 +1,10 @@
+---
+name: api-api-error-handling
+description: Designing error responses for REST APIs
+---
+
+
+
 # API Error Handling
 
 **Use this skill when:**

skills/api/api-rate-limiting.md

@@ -1,3 +1,10 @@
+---
+name: api-api-rate-limiting
+description: Implementing rate limiting for APIs
+---
+
+
+
 # API Rate Limiting
 
 **Use this skill when:**

skills/api/api-versioning.md

@@ -1,3 +1,10 @@
+---
+name: api-api-versioning
+description: Planning API changes and deciding on versioning approach
+---
+
+
+
 # API Versioning
 
 **Scope**: API versioning strategies, breaking changes, deprecation workflow, migration patterns

skills/api/graphql-schema-design.md

@@ -1,3 +1,10 @@
+---
+name: api-graphql-schema-design
+description: Designing GraphQL APIs from scratch
+---
+
+
+
 # GraphQL Schema Design
 
 **Scope**: Schema design, resolvers, N+1 prevention, pagination, authorization

skills/api/rest-api-design.md

@@ -1,3 +1,10 @@
+---
+name: api-rest-api-design
+description: Designing RESTful APIs from scratch
+---
+
+
+
 # REST API Design
 
 **Scope**: RESTful resource modeling, HTTP semantics, URL conventions, status codes

skills/beads-context-strategies.md

@@ -1,3 +1,9 @@
+---
+name: beads-context-strategies
+description: Skill for beads context strategies
+---
+
+
 # Beads Context Management Strategies
 
 **Use this skill when:** Managing Claude Code context while working with Beads, preventing context bloat, or preserving critical workflow state across sessions

skills/beads-dependency-management.md

@@ -1,3 +1,9 @@
+---
+name: beads-dependency-management
+description: bd dep add bd-15 bd-10 --type blocks
+---
+
+
 # Beads Dependency Management
 
 **Use this skill when:** Creating relationships between issues, managing blockers, or organizing work hierarchies