Simplify controller and add E2E tests for status reporting

[yrobla]

Simplify VirtualMCPServer controller by delegating to runtime status reporter

Remove ~1200 lines by delegating backend discovery and health monitoring
from controller to vMCP runtime StatusReporter.

Key changes:

• Remove discoverBackends() from controller reconciliation (~130 lines)
• Fix RBAC permissions to work in all modes (discovered and inline)
• Remove obsolete controller-side discovery tests (807 lines)
• Add comprehensive E2E status reporting tests (408 lines)
• Improve health monitoring with dynamic backend management
• Remove duplicate slow test from yardstick suite (saves 133s per run)

Controller now focuses on infrastructure (RBAC, Deployment, Service).
Runtime handles discovery, health monitoring, and status updates.

Related-to: #3149

Large PR Justification

This is a cleanup pr, that removes substantial lines of code to replace with newer ones. It also includes tests to validate the new behaviour.

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[Copilot]

Pull request overview

This pull request simplifies the VirtualMCPServer controller by removing duplicate backend discovery logic (~130 lines) and delegating all backend discovery and health monitoring to the vMCP runtime via its StatusReporter mechanism. The change aligns with the architectural principle of separation of concerns: the controller manages infrastructure (RBAC, Deployment, Service, ConfigMap), while the vMCP runtime handles backend discovery, health monitoring, and status updates.

Changes:

• Removed discoverBackends() method from controller (delegated to vMCP runtime with K8sReporter)
• Removed controller-side backend discovery tests (virtualmcpserver_discover_backends_test.go)
• Removed integration test TestDiscoverBackendsWithExternalAuthConfigIntegration from virtualmcpserver_externalauth_test.go
• Added comprehensive E2E tests for status reporting (virtualmcp_status_reporting_test.go) with 2 test cases covering backend discovery, health monitoring, and failure recovery
• Added GetMCPServerDeployment helper function for E2E tests

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/e2e/thv-operator/virtualmcp/virtualmcp_status_reporting_test.go	New E2E test suite validating vMCP runtime status reporting for backend discovery and health monitoring
test/e2e/thv-operator/virtualmcp/helpers.go	Added GetMCPServerDeployment helper function to retrieve MCPServer deployments by name
cmd/thv-operator/controllers/virtualmcpserver_externalauth_test.go	Removed TestDiscoverBackendsWithExternalAuthConfigIntegration (170 lines) as backend discovery moved to runtime
cmd/thv-operator/controllers/virtualmcpserver_discover_backends_test.go	Deleted entire file (643 lines of controller-side backend discovery tests)
cmd/thv-operator/controllers/virtualmcpserver_controller.go	Removed discoverBackends method and unused imports (groups, aggregator); added comprehensive documentation explaining responsibility split

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[github-actions]

✅ Large PR justification has been provided. The size review has been dismissed and this PR can now proceed with normal review.

Large PR justification has been provided. Thank you!

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

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[codecov]

Codecov Report

❌ Patch coverage is 64.53202% with 72 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.25%. Comparing base (fc01a6c) to head (c64af60).
⚠️ Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/vmcp/health/monitor.go	73.73%	18 Missing and 8 partials ⚠️
cmd/vmcp/app/commands.go	0.00%	19 Missing ⚠️
pkg/vmcp/server/status_reporting.go	29.41%	10 Missing and 2 partials ⚠️
pkg/vmcp/health/status.go	78.57%	4 Missing and 2 partials ⚠️
pkg/vmcp/errors.go	78.94%	2 Missing and 2 partials ⚠️
pkg/vmcp/client/client.go	0.00%	2 Missing and 1 partial ⚠️
pkg/vmcp/server/server.go	75.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3468      +/-   ##
==========================================
- Coverage   65.27%   65.25%   -0.03%     
==========================================
  Files         399      399              
  Lines       38955    39004      +49     
==========================================
+ Hits        25429    25452      +23     
- Misses      11560    11572      +12     
- Partials     1966     1980      +14     

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[Copilot]

Pull request overview

Copilot reviewed 25 out of 25 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 26 out of 26 changed files in this pull request and generated 6 comments.

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[jhrozek]

I think tightening the RBAC should be a follow-up