test(presets): add unit tests for base and anonmapexec utility functions

[cynox-66]

Summary

This PR adds unit test coverage for the pure-Go utility functions in the presets subsystem as part of the test coverage initiative tracked in #2130.

What is covered

presets/base/common_test.go

Adds comprehensive table-driven tests for core helper functions and types:

• TestAddPolicyLogInfo (6 test cases)

  • Empty policy
  • Policy name only
  • Single tag
  • Multiple tags
  • Severity and message
  • Fully populated policy

  Verifies correct population of:

  • PolicyName
  • Tags
  • ATags
  • Severity
  • Message
  • Type
  • KubeArmorVersion

• TestUpdateMatchPolicy (5 test cases)

  • Zero-value policy
  • Fully populated policy
  • Missing policyName
  • High severity
  • Single tag

  Verifies correct mapping from SecurityPolicy into MatchPolicy, including metadata, severity conversion, message, and tags.

• TestPresetConstants

  • Verifies the values of PRESET_ENFORCER, Audit, and Block.

• TestNsKeyConstruction

  • Verifies construction of NsKey using zero, typical, and maximum namespace values.

presets/anonmapexec/utils_test.go

Adds table-driven tests for utility parsing helpers:

• TestParseProtectionFlags (9 test cases)

  • Zero flags
  • Individual protection flags
  • Combined protection flags
  • High-bit inputs

• TestParseMemoryFlags (11 test cases)

  • Individual memory mapping flags
  • Common flag combinations
  • Full flag combination

Out of Scope

The following components are intentionally excluded because they depend on eBPF code generation, kernel runtime support, or live subsystem integration and cannot be reliably exercised through standard Go unit tests:

• presets/exec/
• presets/filelessexec/
• presets/protectenv/
• presets/protectproc/
• presets/anonmapexec/preset.go
• presets.go

This PR is intentionally limited to deterministic, pure-Go utility code to keep the review focused and self-contained.

Validation

The following validations were completed locally:

# Formatting
gofmt -l presets/base/common_test.go presets/anonmapexec/utils_test.go

# Static analysis
GOOS=linux GOARCH=amd64 go vet ./presets/base/... ./presets/anonmapexec/...

# Package compilation
GOOS=linux GOARCH=amd64 go test -c -o /dev/null ./presets/base/...
GOOS=linux GOARCH=amd64 go test -c -o /dev/null ./presets/anonmapexec/...

• gofmt completed with no formatting issues.
• go vet completed without warnings.
• Both packages compiled successfully for the Linux target.

Manual verification

The following scenarios were verified:

• ParseProtectionFlags() correctly handles zero, individual, combined, and high-bit protection flags.
• ParseMemoryFlags() correctly parses supported memory mapping flags and common flag combinations.
• AddPolicyLogInfo() correctly populates log metadata from empty, partial, and fully populated MatchPolicy inputs.
• UpdateMatchPolicy() correctly maps SecurityPolicy metadata, severity, message, and tags into MatchPolicy.
• Preset constants retain their expected values.
• NsKey construction behaves correctly across representative namespace values.

Additional information

This PR is part of the ongoing unit test coverage effort tracked in #2130.

It continues the existing coverage series following:

• PR tests: add unit tests for common package #2700 (common)
• PR test(cert): add unit tests for TLS certificate infrastructure #2709 (cert)
• PR test(config): add unit tests for config package #2711 (config)

The goal is to incrementally improve coverage across independent packages using small, reviewable PRs without modifying production code.