Surface and filter ai classification on results show(AST-178033)

[cx-sumit-morchhale]

Summary

• Surfaces the aiClassification field (TP/FP/UNCLASSIFIED/NOT_ANALYZED) that ast-results now returns on GET /api/results for SAST results (AST-175453) into both the CLI's JSON and SARIF reports — previously silently dropped since ScanResultData had no matching field.
• Documents the existing --filter "ai-classification=TP;FP" pass-through in results show's help text (filtering already worked by accident via the generic --filter mechanism; this just makes it discoverable).
• Absent/omitted when the API omits the key (non-SAST result, or the phase-2 flag off for the tenant) — no client-side feature-flag gate needed, the CLI just reflects whatever ast-results sends.

Changes

• internal/wrappers/results-json.go — add AIClassification *string (omitempty) to ScanResultData.
• internal/wrappers/results-sarif.go — add AIClassification *string (omitempty) to SarifResultProperties.
• internal/commands/result.go — populate SarifResultProperties.AIClassification in parseSarifResultSast when present; list ai-classification in filterResultsListFlagUsage.
• internal/params/flags.go — add AIClassificationQueryParam constant.
• internal/wrappers/mock/results-mock.go — seed one mock SAST result with a classification for test coverage.
• internal/commands/result_test.go — cover present/absent cases for both JSON and SARIF output.

Out of scope

• sonar and gl-sast reports (externally-owned schemas, no field for this) and pdf (server-rendered) — unchanged.