refactor: wave 1 - extract leaf modules, rename catch-all files, split index.ts hooks

- Split 25+ index.ts files into hook.ts + extracted modules
- Rename all catch-all utils.ts/helpers.ts to domain-specific names
- Split src/tools/lsp/ into ~15 focused modules
- Split src/tools/delegate-task/ into ~18 focused modules
- Separate shared types from implementation
- 155 files changed, 60+ new files created
- All typecheck clean, 61 tests pass

src/agents/builtin-agents/general-agents.ts

@@ -0,0 +1,108 @@
+import type { AgentConfig } from "@opencode-ai/sdk"
+import type { BuiltinAgentName, AgentOverrides, AgentPromptMetadata } from "../types"
+import type { CategoryConfig, GitMasterConfig } from "../../config/schema"
+import type { BrowserAutomationProvider } from "../../config/schema"
+import type { AvailableAgent } from "../dynamic-agent-prompt-builder"
+import { AGENT_MODEL_REQUIREMENTS, isModelAvailable } from "../../shared"
+import { buildAgent, isFactory } from "../agent-builder"
+import { applyCategoryOverride, applyOverrides } from "./agent-overrides"
+import { applyEnvironmentContext } from "./environment-context"
+import { applyModelResolution } from "./model-resolution"
+
+export function collectPendingBuiltinAgents(input: {
+  agentSources: Record<BuiltinAgentName, import("../agent-builder").AgentSource>
+  agentMetadata: Partial<Record<BuiltinAgentName, AgentPromptMetadata>>
+  disabledAgents: string[]
+  agentOverrides: AgentOverrides
+  directory?: string
+  systemDefaultModel?: string
+  mergedCategories: Record<string, CategoryConfig>
+  gitMasterConfig?: GitMasterConfig
+  browserProvider?: BrowserAutomationProvider
+  uiSelectedModel?: string
+  availableModels: Set<string>
+  disabledSkills?: Set<string>
+}): { pendingAgentConfigs: Map<string, AgentConfig>; availableAgents: AvailableAgent[] } {
+  const {
+    agentSources,
+    agentMetadata,
+    disabledAgents,
+    agentOverrides,
+    directory,
+    systemDefaultModel,
+    mergedCategories,
+    gitMasterConfig,
+    browserProvider,
+    uiSelectedModel,
+    availableModels,
+    disabledSkills,
+  } = input
+
+  const availableAgents: AvailableAgent[] = []
+  const pendingAgentConfigs: Map<string, AgentConfig> = new Map()
+
+  for (const [name, source] of Object.entries(agentSources)) {
+    const agentName = name as BuiltinAgentName
+
+    if (agentName === "sisyphus") continue
+    if (agentName === "hephaestus") continue
+    if (agentName === "atlas") continue
+    if (disabledAgents.some((name) => name.toLowerCase() === agentName.toLowerCase())) continue
+
+    const override = agentOverrides[agentName]
+      ?? Object.entries(agentOverrides).find(([key]) => key.toLowerCase() === agentName.toLowerCase())?.[1]
+    const requirement = AGENT_MODEL_REQUIREMENTS[agentName]
+
+    // Check if agent requires a specific model
+    if (requirement?.requiresModel && availableModels) {
+      if (!isModelAvailable(requirement.requiresModel, availableModels)) {
+        continue
+      }
+    }
+
+    const isPrimaryAgent = isFactory(source) && source.mode === "primary"
+
+    const resolution = applyModelResolution({
+      uiSelectedModel: (isPrimaryAgent && !override?.model) ? uiSelectedModel : undefined,
+      userModel: override?.model,
+      requirement,
+      availableModels,
+      systemDefaultModel,
+    })
+    if (!resolution) continue
+    const { model, variant: resolvedVariant } = resolution
+
+    let config = buildAgent(source, model, mergedCategories, gitMasterConfig, browserProvider, disabledSkills)
+
+    // Apply resolved variant from model fallback chain
+    if (resolvedVariant) {
+      config = { ...config, variant: resolvedVariant }
+    }
+
+    // Expand override.category into concrete properties (higher priority than factory/resolved)
+    const overrideCategory = (override as Record<string, unknown> | undefined)?.category as string | undefined
+    if (overrideCategory) {
+      config = applyCategoryOverride(config, overrideCategory, mergedCategories)
+    }
+
+    if (agentName === "librarian") {
+      config = applyEnvironmentContext(config, directory)
+    }
+
+    config = applyOverrides(config, override, mergedCategories)
+
+    // Store for later - will be added after sisyphus and hephaestus
+    pendingAgentConfigs.set(name, config)
+
+    const metadata = agentMetadata[agentName]
+    if (metadata) {
+      availableAgents.push({
+        name: agentName,
+        description: config.description ?? "",
+        metadata,
+      })
+    }
+  }
+
+  return { pendingAgentConfigs, availableAgents }
+}