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/sisyphus-agent.ts

@@ -0,0 +1,81 @@
+import type { AgentConfig } from "@opencode-ai/sdk"
+import type { AgentOverrides } from "../types"
+import type { CategoriesConfig, CategoryConfig } from "../../config/schema"
+import type { AvailableAgent, AvailableCategory, AvailableSkill } from "../dynamic-agent-prompt-builder"
+import { AGENT_MODEL_REQUIREMENTS, isAnyFallbackModelAvailable } from "../../shared"
+import { applyEnvironmentContext } from "./environment-context"
+import { applyOverrides } from "./agent-overrides"
+import { applyModelResolution, getFirstFallbackModel } from "./model-resolution"
+import { createSisyphusAgent } from "../sisyphus"
+
+export function maybeCreateSisyphusConfig(input: {
+  disabledAgents: string[]
+  agentOverrides: AgentOverrides
+  uiSelectedModel?: string
+  availableModels: Set<string>
+  systemDefaultModel?: string
+  isFirstRunNoCache: boolean
+  availableAgents: AvailableAgent[]
+  availableSkills: AvailableSkill[]
+  availableCategories: AvailableCategory[]
+  mergedCategories: Record<string, CategoryConfig>
+  directory?: string
+  userCategories?: CategoriesConfig
+}): AgentConfig | undefined {
+  const {
+    disabledAgents,
+    agentOverrides,
+    uiSelectedModel,
+    availableModels,
+    systemDefaultModel,
+    isFirstRunNoCache,
+    availableAgents,
+    availableSkills,
+    availableCategories,
+    mergedCategories,
+    directory,
+  } = input
+
+  const sisyphusOverride = agentOverrides["sisyphus"]
+  const sisyphusRequirement = AGENT_MODEL_REQUIREMENTS["sisyphus"]
+  const hasSisyphusExplicitConfig = sisyphusOverride !== undefined
+  const meetsSisyphusAnyModelRequirement =
+    !sisyphusRequirement?.requiresAnyModel ||
+    hasSisyphusExplicitConfig ||
+    isFirstRunNoCache ||
+    isAnyFallbackModelAvailable(sisyphusRequirement.fallbackChain, availableModels)
+
+  if (disabledAgents.includes("sisyphus") || !meetsSisyphusAnyModelRequirement) return undefined
+
+  let sisyphusResolution = applyModelResolution({
+    uiSelectedModel: sisyphusOverride?.model ? undefined : uiSelectedModel,
+    userModel: sisyphusOverride?.model,
+    requirement: sisyphusRequirement,
+    availableModels,
+    systemDefaultModel,
+  })
+
+  if (isFirstRunNoCache && !sisyphusOverride?.model && !uiSelectedModel) {
+    sisyphusResolution = getFirstFallbackModel(sisyphusRequirement)
+  }
+
+  if (!sisyphusResolution) return undefined
+  const { model: sisyphusModel, variant: sisyphusResolvedVariant } = sisyphusResolution
+
+  let sisyphusConfig = createSisyphusAgent(
+    sisyphusModel,
+    availableAgents,
+    undefined,
+    availableSkills,
+    availableCategories
+  )
+
+  if (sisyphusResolvedVariant) {
+    sisyphusConfig = { ...sisyphusConfig, variant: sisyphusResolvedVariant }
+  }
+
+  sisyphusConfig = applyOverrides(sisyphusConfig, sisyphusOverride, mergedCategories)
+  sisyphusConfig = applyEnvironmentContext(sisyphusConfig, directory)
+
+  return sisyphusConfig
+}