Simplify seed data configuration by removing command line flags and renaming environment variable (#175)

This PR simplifies the seed data import configuration based on
maintainer feedback by removing command line flags and using a clearer
environment variable name.

## Key Changes

### Configuration Simplification
- **Renamed**: `MCP_REGISTRY_SEED_FILE_PATH` → `MCP_REGISTRY_SEED_FROM`
- **Removed**: `--seed-file-path` command line flag to eliminate
configuration complexity

### Improved User Experience
Users now configure seed data import using a single, clear environment
variable:

```bash
# Before (multiple ways to configure)
MCP_REGISTRY_SEED_FILE_PATH=data/seed.json ./registry
./registry --seed-file-path=data/seed.json

# After (simplified single method)
MCP_REGISTRY_SEED_FROM=data/seed.json ./registry
```

### Registry Composability
The composability workflow is now simplified while maintaining all
functionality:

```bash
# Start first registry with seed data
MCP_REGISTRY_SEED_FROM=data/seed.json ./registry

# Start second registry importing from first via pagination
MCP_REGISTRY_SEED_FROM=http://localhost:8080 ./registry
```

## Technical Implementation
- Maintains full backward compatibility for import functionality
- All existing seed data sources continue to work (local files, HTTP
URLs, registry URLs)
- Automatic pagination through `/v0/servers` endpoint remains unchanged
- Configurable delays between requests preserved

## Benefits
- **Reduced complexity**: Single configuration method instead of
multiple
- **Clearer naming**: `SEED_FROM` better describes the source of seed
data
- **Easier maintenance**: Fewer configuration paths to test and document
- **Consistent patterns**: Aligns with other environment-variable-only
configuration

All existing functionality is preserved while providing a cleaner, more
maintainable configuration interface.

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Avinash Sridhar <sridharavinash@users.noreply.github.com>
Co-authored-by: Toby Padilla <toby@toby.sh>
Co-authored-by: toby <83556+toby@users.noreply.github.com>

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ on:
     branches: [ main ]
 
 env:
-  GO_VERSION: '1.23.x'
+  GO_VERSION: '1.24.x'
 
 jobs:
   # Build, Lint, and Validate
@@ -17,38 +17,38 @@ jobs:
     steps:
     - name: Checkout code
       uses: actions/checkout@v4
-      
+
     - name: Set up Go
       uses: actions/setup-go@v5
       with:
         go-version: ${{ env.GO_VERSION }}
-        
+
     - name: Cache Go modules
       uses: actions/cache@v4
       with:
         path: |
           ~/.cache/go-build
           ~/go/pkg/mod
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+        key: ${{ runner.os }}-go-${{ github.sha }}-${{ hashFiles('**/go.sum', '.golangci.yml') }}
         restore-keys: |
           ${{ runner.os }}-go-
-          
+
     - name: Download dependencies
       run: go mod download
-      
+
     - name: Install golangci-lint
       run: |
         curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v2.3.1
-        
+
     - name: Run lint
       run: make lint
-      
+
     - name: Validate schemas and examples
       run: make validate
-      
+
     - name: Build application
       run: make build
-        
+
     - name: Check for vulnerabilities
       run: |
         go install golang.org/x/vuln/cmd/govulncheck@latest
@@ -61,12 +61,12 @@ jobs:
     steps:
     - name: Checkout code
       uses: actions/checkout@v4
-      
+
     - name: Set up Go
       uses: actions/setup-go@v5
       with:
         go-version: ${{ env.GO_VERSION }}
-        
+
     - name: Cache Go modules
       uses: actions/cache@v4
       with:
@@ -76,13 +76,13 @@ jobs:
         key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
         restore-keys: |
           ${{ runner.os }}-go-
-          
+
     - name: Download dependencies
       run: go mod download
-      
+
     - name: Run all tests
       run: make test-all
-        
+
     - name: Upload coverage to Codecov
       uses: codecov/codecov-action@v4
       with: