refactor: pluginize text cleaning and tool NoMemory control

- SDK: ToolDef.NoMemory field, PluginSDK.RegisterTextCleaner/TextCleaners
- Registry: aggregate text cleaners from plugins, expose CleanText()
- Memory: replace hardcoded QQ regex CleanTemplateText with dynamic CleanText/SetTextCleaner
- StageHost: add ToolDef(name) lookup
- eventloop: check ToolDef.NoMemory before emitMemoryCandidate
- context/Prune: replace hardcoded agentcli/terminal source filter with ToolsUsed NoMemory check
- agentcli/cmd: mark tools with NoMemory: true
- main.go: wire memory.SetTextCleaner(pluginReg.CleanText)

_sdk_local/meta/meta.go

@@ -0,0 +1,23 @@
+// Package meta 收集 HomeAgent SDK 的全部元数据。
+// 版本号应与核心 meta.Version 保持一致。
+package meta
+
+var (
+	// Version 是 HomeAgent SDK 版本号。
+	// 通过 `-ldflags="-X gitcode.com/JianFeeeee/homeagent-sdk/meta.Version=vX.Y.Z"` 注入。
+	Version = "0.7.1"
+
+	// Commit 是构建时的 Git commit hash。
+	Commit = "unknown"
+
+	// BuildTime 是构建时间。
+	BuildTime = "unknown"
+
+	// SDKName 是 SDK 名称。
+	SDKName = "HomeAgent SDK"
+)
+
+// FullVersion 返回完整的版本字符串。
+func FullVersion() string {
+	return SDKName + " v" + Version + " (" + Commit + ")"
+}