feat(preview): proxy Labelary through Rust, tighten desktop CSP

The webview no longer fetches previews (CSP drops http:/https:); the Rust
proxy validates host/path and blocks redirects. The API key is a host-bound,
rust-only keychain credential the proxy reads itself, so it never enters
webview memory and can't be replayed against a foreign host.

Author: u8array

src-tauri/Cargo.lock

@@ -21,6 +21,9 @@ tauri = { version = "2.11.3", features = [] }
 serde_json = "1"
 serde = { version = "1", features = ["derive"] }
 tokio = { version = "1", features = ["net", "time", "io-util", "rt"] }
+# Preview proxy only (redirects disabled there); rustls to match sqlx.
+reqwest = { version = "0.12", default-features = false, features = ["rustls-tls"] }
+base64 = "0.22"
 # Stream a query's rows (db.rs) instead of fetch_all so a huge result is bounded
 # by a byte budget and errors instead of OOMing. Already transitive via sqlx;
 # tokio-stream keeps us in the tokio ecosystem we already depend on directly.

src-tauri/Cargo.toml

@@ -8,9 +8,9 @@ drifts from the locked dependencies.
 
 ## Overview
 
-- MIT License (443)
+- MIT License (445)
 - Unicode License v3 (19)
-- Apache License 2.0 (6)
+- Apache License 2.0 (7)
 - BSD 3-Clause "New" or "Revised" License (5)
 - Mozilla Public License 2.0 (5)
 - ISC License (3)
@@ -883,6 +883,7 @@ Apache License
 
 Used by:
 
+- [ryu 1.0.23](https://github.com/dtolnay/ryu)
 - [sync_wrapper 1.0.2](https://github.com/Actyx/sync_wrapper)
 ````
 Apache License
@@ -2365,6 +2366,40 @@ DEALINGS IN THE SOFTWARE.
 
 Used by:
 
+- [serde_urlencoded 0.7.1](https://github.com/nox/serde_urlencoded)
+````
+Copyright (c) 2016 Anthony Ramine
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+
+````
+
+### MIT License
+
+Used by:
+
 - [webkit2gtk-sys 2.0.2](https://github.com/tauri-apps/webkit2gtk-rs)
 ````
 Copyright (c) 2016 Boucher, Antoni <bouanto@zoho.com>
@@ -2659,6 +2694,35 @@ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
 IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 DEALINGS IN THE SOFTWARE.
 
+````
+
+### MIT License
+
+Used by:
+
+- [reqwest 0.12.28](https://github.com/seanmonstar/reqwest)
+````
+Copyright (c) 2016-2025 Sean McArthur
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+
 ````
 
 ### MIT License