refactor(agent): remove deprecated model fetcher cache (#3433)

Co-authored-by: Kandev Agent <agent@kandev.dev>

apps/backend/internal/agent/settings/controller/controller.go

@@ -14,7 +14,6 @@ import (
 	"github.com/kandev/kandev/internal/agent/managedruntime"
 	"github.com/kandev/kandev/internal/agent/mcpconfig"
 	"github.com/kandev/kandev/internal/agent/registry"
-	"github.com/kandev/kandev/internal/agent/settings/modelfetcher"
 	"github.com/kandev/kandev/internal/agent/settings/store"
 	"github.com/kandev/kandev/internal/common/logger"
 	"github.com/kandev/kandev/internal/secrets"
@@ -71,7 +70,6 @@ type Controller struct {
 	automationDeps              AutomationDependencyChecker
 	utilityDeps                 UtilityDependencyChecker
 	mcpService                  *mcpconfig.Service
-	modelCache                  *modelfetcher.Cache
 	hostUtility                 hostUtilityProvider
 	jobStore                    *JobStore
 	updateJobStore              *AgentUpdateJobStore
@@ -256,7 +254,6 @@ func NewController(repo store.Repository, discoveryRegistry *discovery.Registry,
 		agentRegistry:             agentRegistry,
 		sessionChecker:            sessionChecker,
 		mcpService:                mcpconfig.NewService(repo),
-		modelCache:                modelfetcher.NewCache(),
 		logger:                    log.WithFields(zap.String("component", "agent-settings-controller")),
 		runtimeUpdateStatusCache:  make(map[string]runtimeUpdateStatusCacheEntry),
 		runtimeUpdateStatusNow:    time.Now,

apps/backend/internal/agent/settings/controller/controller_test.go

@@ -14,7 +14,6 @@ import (
 	"github.com/kandev/kandev/internal/agent/managedruntime"
 	"github.com/kandev/kandev/internal/agent/registry"
 	"github.com/kandev/kandev/internal/agent/settings/dto"
-	"github.com/kandev/kandev/internal/agent/settings/modelfetcher"
 	"github.com/kandev/kandev/internal/agent/usage"
 	"github.com/kandev/kandev/internal/common/logger"
 )
@@ -112,7 +111,6 @@ func newTestController(agentList map[string]agents.Agent) *Controller {
 	}
 	return &Controller{
 		agentRegistry: reg,
-		modelCache:    modelfetcher.NewCache(),
 		logger:        log,
 	}
 }

apps/backend/internal/agent/settings/modelfetcher/cache.go

@@ -1,99 +0,0 @@
-package modelfetcher
-
-import (
-	"sync"
-	"time"
-)
-
-// Model is a simple descriptor retained here so CacheEntry can remain typed.
-// Static agent model lists have been removed — models now come from the host
-// utility capability cache. This package is deprecated and kept only as a
-// shim for legacy callers until they migrate.
-type Model struct {
-	ID          string
-	Name        string
-	Description string
-	IsDefault   bool
-}
-
-const (
-	defaultTTL  = 10 * time.Second
-	maxCacheAge = 1 * time.Minute
-)
-
-// CacheEntry holds cached model data for an agent
-type CacheEntry struct {
-	Models    []Model
-	CachedAt  time.Time
-	ExpiresAt time.Time
-	Error     error
-}
-
-// IsValid returns true if the cache entry is still valid
-func (e *CacheEntry) IsValid() bool {
-	return time.Now().Before(e.ExpiresAt) && e.Error == nil
-}
-
-// IsStale returns true if the cache entry is stale but still usable
-func (e *CacheEntry) IsStale() bool {
-	now := time.Now()
-	return now.After(e.ExpiresAt) && now.Before(e.CachedAt.Add(maxCacheAge))
-}
-
-// Cache provides thread-safe caching for dynamic models
-type Cache struct {
-	entries map[string]*CacheEntry
-	mu      sync.RWMutex
-	ttl     time.Duration
-}
-
-// NewCache creates a new model cache
-func NewCache() *Cache {
-	return &Cache{
-		entries: make(map[string]*CacheEntry),
-		ttl:     defaultTTL,
-	}
-}
-
-// Get returns the cached models for an agent if available
-func (c *Cache) Get(agentName string) (*CacheEntry, bool) {
-	c.mu.RLock()
-	defer c.mu.RUnlock()
-
-	entry, exists := c.entries[agentName]
-	if !exists {
-		return nil, false
-	}
-
-	return entry, true
-}
-
-// Set caches the models for an agent
-func (c *Cache) Set(agentName string, models []Model, err error) {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	now := time.Now()
-	c.entries[agentName] = &CacheEntry{
-		Models:    models,
-		CachedAt:  now,
-		ExpiresAt: now.Add(c.ttl),
-		Error:     err,
-	}
-}
-
-// Invalidate removes the cache entry for an agent
-func (c *Cache) Invalidate(agentName string) {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	delete(c.entries, agentName)
-}
-
-// Clear removes all cache entries
-func (c *Cache) Clear() {
-	c.mu.Lock()
-	defer c.mu.Unlock()
-
-	c.entries = make(map[string]*CacheEntry)
-}

config/architecture-lint/compatibility-ledger.json

@@ -13,18 +13,6 @@
       "removal_condition": "All callers import the owning agents package and no registry compatibility type alias remains.",
       "target_removal_date": "2027-02-01"
     },
-    {
-      "id": "agent-model-fetcher-shim",
-      "locator": {
-        "path": "apps/backend/internal/agent/settings/modelfetcher/cache.go",
-        "marker": "// shim for legacy callers until they migrate."
-      },
-      "reason": "Legacy callers still require the old typed cache while model discovery moves to the host utility capability cache.",
-      "owner": "backend agent-settings maintainers",
-      "introduced_on": "2026-04-15",
-      "removal_condition": "No production package imports internal/agent/settings/modelfetcher and the shim package can be deleted.",
-      "target_removal_date": "2027-02-01"
-    },
     {
       "id": "passthrough-stdin-writes-legacy-view",
       "locator": {