fix: POST for file creation (Gitea 1.25+), add edit_issue tool, persist poll state

- files.ts: Use POST for new files, PUT for updates (Gitea 1.25 requires this)
- issues.ts: Add editIssue() for state/title/body changes
- write-tools.ts: Add gitea_edit_issue tool (open/close/edit issues)
- webhook/server.ts: Persist lastPollAt to disk to prevent duplicate
  events on reload; use followUp delivery to queue events during LLM turns
- index.ts: Use deliverAs:'followUp' for sendUserMessage

pi-extension/tools/write-tools.ts

@@ -161,6 +161,32 @@ export default function (pi: ExtensionAPI) {
 		},
 	});
 
+	pi.registerTool({
+		name: "gitea_edit_issue",
+		label: "Gitea: Edit Issue",
+		description: "Edit an issue — change title, body, or state (open/closed). Use this to close issues when work is done.",
+		parameters: Type.Object({
+			owner: Type.Optional(Type.String({ description: `Repo owner (default: ${client.defaultOwner})` })),
+			repo: Type.Optional(Type.String({ description: `Repo name (default: ${client.defaultRepo})` })),
+			index: Type.Number({ description: "Issue number" }),
+			title: Type.Optional(Type.String({ description: "New title" })),
+			body: Type.Optional(Type.String({ description: "New body (Markdown)" })),
+			state: Type.Optional(Type.String({ description: "New state: 'open' or 'closed'" })),
+		}),
+		async execute(_id, params) {
+			const { owner, repo } = client.resolve(params.owner, params.repo);
+			const updated = await issues.editIssue(client, owner, repo, params.index, {
+				title: params.title,
+				body: params.body,
+				state: params.state as "open" | "closed" | undefined,
+			});
+			return {
+				content: [{ type: "text", text: `Issue #${updated.number} updated (state: ${updated.state}): ${updated.html_url}` }],
+				details: { issue: updated },
+			};
+		},
+	});
+
 	// ── Pull Requests ──
 
 	pi.registerTool({