Implement T001 baseline benchmarks for application bootstrap and service lookup performance

[Copilot]

This PR implements Task T001: Baseline Benchmark as specified in the performance testing tasks spec. The benchmarks establish baseline performance metrics for the modular framework prior to dynamic reload and health aggregator implementations.

What's Added

Created internal/benchmark/benchmark_baseline_test.go with comprehensive baseline benchmarks:

• BenchmarkApplicationBootstrap: Measures full application lifecycle timing (Build+Init+Start+Stop) with multiple mock modules to simulate realistic startup scenarios
• BenchmarkServiceLookup: Benchmarks service registry performance for both by-name and by-interface lookup patterns with 100 registered services
• BenchmarkServiceLookupWithBatchRegistration: Tests service lookup performance when services are registered in batches, simulating module initialization patterns

Implementation Details

The benchmarks follow Go testing best practices:

• Use b.ReportAllocs() for allocation reporting
• Call b.ResetTimer() after setup to exclude preparation time
• Lightweight design with no external network dependencies and minimal resource usage
• Proper cleanup to avoid resource leaks between benchmark iterations

The file includes:

• //go:build planned tag so benchmarks won't run by default until the later execution phase
• Comprehensive documentation referencing the T001 task specification
• Mock implementations (BenchmarkModule, MockStorage, TestLogger) that simulate realistic module behavior without external dependencies

Usage

# Run all baseline benchmarks
go test -tags=planned -run=^$ -bench=. ./internal/benchmark/

# Run specific benchmark
go test -tags=planned -run=^$ -bench=BenchmarkApplicationBootstrap ./internal/benchmark/

Without the build tag, the benchmarks are properly hidden:

go test -bench=. ./internal/benchmark/
# Returns: build constraints exclude all Go files

Verification

• ✅ File compiles without errors
• ✅ Benchmarks run successfully with realistic performance metrics
• ✅ No golangci-lint violations
• ✅ Build tag correctly hides benchmarks by default
• ✅ All existing tests continue to pass
• ✅ Proper allocation reporting and timing measurement

These benchmarks will serve as the performance baseline for measuring the impact of future dynamic reload and health aggregator features.

Created from VS Code via the GitHub Pull Request extension.

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[Copilot]

Pull Request Overview

This PR implements Task T001: Baseline Benchmark to establish performance metrics for the modular framework before implementing dynamic reload and health aggregator features. The implementation creates comprehensive benchmarks for application bootstrap and service lookup operations.

Key changes:

• Adds baseline benchmarks for application lifecycle performance measurement
• Implements service registry lookup performance tests with realistic service counts
• Creates mock implementations to simulate module behavior without external dependencies

[Copilot]

The documentation is incomplete - it mentions only 2 benchmarks but the file actually contains 3 benchmarks (including BenchmarkServiceLookupWithBatchRegistration). Update the comment to list all three benchmarks for accuracy.

Suggested change

	// - BenchmarkServiceLookup: Benchmarks repeated service lookup by interface/name
	// - BenchmarkServiceLookup: Benchmarks repeated service lookup by interface/name
	// - BenchmarkServiceLookupWithBatchRegistration: Benchmarks service lookup performance with batch service registration

[Copilot]

This comment is misleading - Init() is not equivalent to the Build phase. The Build phase is the application creation (NewApplication), while Init() is the initialization phase that comes after building. The comment should accurately describe Init() as the initialization phase.

Suggested change

	// Initialize the application (equivalent to Build phase)
	// Initialize the application (initialization phase after building)