feat: support pull requests

Support for pull requests, it's not standard in NIPs yet[1] but there must be
two clients that support it to be included in NIPs, n34 is one of them.

This support:
- Create a new PR `n34 pr new`
- Update PR tip `n34 pr update`
- View a PR `n34 pr view`
- List PRs `n34 pr list`
- Add `PR` and `PR-update` kinds as roots in `NostrClient::find_root`
- Support issuing statuses for PRs
- Support GRASP PR and PR-update
- Update the docs

[1] https://github.com/nostr-protocol/nips/pull/1966

src/cli/utils.rs

@@ -0,0 +1,45 @@
+// n34 - A CLI to interact with NIP-34 and other stuff related to codes in nostr
+// Copyright (C) 2025 Awiteb <a@4rs.nl>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://gnu.org/licenses/gpl-3.0.html>.
+
+use std::io::{self, Write};
+
+/// Displays the given prompt and reads a line of input from the user.
+pub fn read_line(prompt: &str) -> io::Result<String> {
+    {
+        let mut stdout = io::stdout().lock();
+
+        write!(&mut stdout, "{prompt}: ")?;
+        _ = stdout.flush();
+    }
+    let mut user_input = String::new();
+    io::stdin().read_line(&mut user_input)?;
+    Ok(user_input.trim().to_owned())
+}
+
+/// Prompts the user with a message and repeatedly asks until they enter a valid
+/// boolean response. Recognizes "yes", "y", "true" for `true` and "no", "n",
+/// "false" for `false`.
+pub fn prompt_bool(prompt: &str) -> io::Result<bool> {
+    loop {
+        let user_input = read_line(prompt)?.to_ascii_lowercase();
+
+        match user_input.as_str() {
+            "yes" | "y" | "true" => return Ok(true),
+            "no" | "n" | "false" => return Ok(false),
+            _ => continue,
+        }
+    }
+}