Add draft C++ language bindings for payjoin-ffi

.codespellrc

@@ -1,3 +1,3 @@
 [codespell]
-skip = .git,target,Cargo.toml,Cargo.lock,Cargo-minimal.lock,Cargo-recent.lock,package-lock.json,./fuzz/corpus
+skip = .git,target,Cargo.toml,Cargo.lock,Cargo-minimal.lock,Cargo-recent.lock,package-lock.json,./fuzz/corpus,./payjoin-ffi/cpp/src,./payjoin-ffi/cpp/build
 ignore-words-list = crate,ser,ot,re-useable

.github/workflows/cpp.yml

@@ -0,0 +1,31 @@
+name: Build and Test Cpp
+on:
+  workflow_run:
+    workflows: ["Flake maintenance"]
+    types: [requested]
+    branches:
+      - "update_flake_lock_action"
+  pull_request:
+    paths:
+      - payjoin-ffi/**
+      # The jobs run inside the flake's dev shell, so changes to the flake
+      # change this workflow's environment.
+      - flake.nix
+      - flake.lock
+
+jobs:
+  build-cpp-and-test:
+    name: "Build and test cpp"
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-26.04, macos-latest]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+      - name: "Use cache"
+        uses: Swatinem/rust-cache@v2
+      - name: Set up nix
+        uses: ./.github/actions/setup-nix
+      - name: "Build and test"
+        run: nix develop .#cpp -c bash ./payjoin-ffi/cpp/contrib/test.sh

Cargo-minimal.lock

@@ -61,7 +61,7 @@ checksum = "891477e0c6a8957309ee5c45a6368af3ae14bb510732d2684ffa19af310920f9"
 dependencies = [
  "getrandom 0.2.10",
  "once_cell",
- "version_check",
+ "version_check 0.9.4",
 ]
 
 [[package]]
@@ -72,7 +72,7 @@ checksum = "77c3a9648d43b9cd48db467b3f87fdd6e146bcc88ab0180006cef2179fe11d01"
 dependencies = [
  "cfg-if 1.0.0",
  "once_cell",
- "version_check",
+ "version_check 0.9.4",
  "zerocopy 0.7.31",
 ]
 
@@ -184,6 +184,19 @@ version = "0.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8da52d66c7071e2e3fa2a1e5c6d088fec47b593032b254f5e980de8ea54454d6"
 
+[[package]]
+name = "askama"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47cbc3cf73fa8d9833727bbee4835ba5c421a0d65b72daf9a7b5d0e0f9cfb57e"
+dependencies = [
+ "askama_derive 0.12.0",
+ "askama_escape",
+ "humansize",
+ "num-traits",
+ "percent-encoding",
+]
+
 [[package]]
 name = "askama"
 version = "0.13.0"
@@ -210,6 +223,22 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "askama_derive"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e80b5ad1afe82872b7aa3e9de9b206ecb85584aa324f0f60fa4c903ce935936b"
+dependencies = [
+ "basic-toml",
+ "mime",
+ "mime_guess",
+ "nom",
+ "proc-macro2",
+ "quote",
+ "serde",
+ "syn 1.0.74",
+]
+
 [[package]]
 name = "askama_derive"
 version = "0.13.0"
@@ -244,6 +273,12 @@ dependencies = [
  "syn 2.0.87",
 ]
 
+[[package]]
+name = "askama_escape"
+version = "0.10.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "619743e34b5ba4e9703bba34deac3427c72507c7159f5fd030aea8cac0cfe341"
+
 [[package]]
 name = "askama_parser"
 version = "0.13.0"
@@ -804,9 +839,9 @@ dependencies = [
 
 [[package]]
 name = "camino"
-version = "1.0.8"
+version = "1.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07fd178c5af4d59e83498ef15cf3f154e1a6f9d091270cb86283c65ef44e9ef0"
+checksum = "c59e92b5a388f549b863a7bea62612c09f24c8393560709a54558a9abdfb3b9c"
 dependencies = [
  "serde",
 ]
@@ -1625,7 +1660,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "501466ecc8a30d1d3b7fc9229b122b2ce8ed6e9d9223f1138d4babb253e51817"
 dependencies = [
  "typenum",
- "version_check",
+ "version_check 0.9.4",
 ]
 
 [[package]]
@@ -1883,6 +1918,15 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "05842d0d43232b23ccb7060ecb0f0626922c21f30012e97b767b30afd4a5d4b9"
 
+[[package]]
+name = "humansize"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e12090e3b87a266157c30eef7ee8f430f4226feb8dd970cccea2cc67f52f70e"
+dependencies = [
+ "libm",
+]
+
 [[package]]
 name = "hyper"
 version = "1.8.0"
@@ -2153,6 +2197,12 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "libm"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "292a948cd991e376cf75541fe5b97a1081d713c618b4f1b9500f8844e49eb565"
+
 [[package]]
 name = "libredox"
 version = "0.1.3"
@@ -2250,6 +2300,16 @@ version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2a60c7ce501c71e03a9c9c0d35b861413ae925bd979cc7a4e30d060069aaac8d"
 
+[[package]]
+name = "mime_guess"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d729cf45eaf996831fe7143af04190187ab3ee2a72ea96bd00958d1fae822a9d"
+dependencies = [
+ "mime",
+ "unicase",
+]
+
 [[package]]
 name = "minimal-lexical"
 version = "0.2.0"
@@ -2344,7 +2404,7 @@ checksum = "1b1d11e1ef389c76fe5b81bcaf2ea32cf88b62bc494e19f493d0b30e7a930109"
 dependencies = [
  "memchr",
  "minimal-lexical",
- "version_check",
+ "version_check 0.9.4",
 ]
 
 [[package]]
@@ -2639,6 +2699,7 @@ dependencies = [
  "thiserror 2.0.18",
  "tokio",
  "uniffi",
+ "uniffi-bindgen-cpp",
  "uniffi-bindgen-cs",
  "uniffi-dart",
  "url",
@@ -2901,7 +2962,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "syn 1.0.74",
- "version_check",
+ "version_check 0.9.4",
 ]
 
 [[package]]
@@ -2914,7 +2975,7 @@ dependencies = [
  "quote",
  "syn 1.0.74",
  "syn-mid",
- "version_check",
+ "version_check 0.9.4",
 ]
 
 [[package]]
@@ -4201,6 +4262,12 @@ dependencies = [
  "winnow 0.7.13",
 ]
 
+[[package]]
+name = "topological-sort"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ea68304e134ecd095ac6c3574494fc62b909f416c4fca77e440530221e549d3d"
+
 [[package]]
 name = "tower"
 version = "0.5.2"
@@ -4370,6 +4437,15 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3ac9567e27ca9fc45bac22f987fd62547b0ac65d2e6502dfc09cdab7dbdba31f"
 
+[[package]]
+name = "unicase"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a84e5511b2a947f3ae965dcb29b13b7b1691b6e7332cf5dbc1744138d5acb7f6"
+dependencies = [
+ "version_check 0.1.0",
+]
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.5"
@@ -4430,6 +4506,26 @@ dependencies = [
  "uniffi_pipeline",
 ]
 
+[[package]]
+name = "uniffi-bindgen-cpp"
+version = "0.8.0+v0.30.0"
+source = "git+https://github.com/chavic/uniffi-bindgen-cpp?rev=830943d09ba1840e69e72caba030c03b5287cb40#830943d09ba1840e69e72caba030c03b5287cb40"
+dependencies = [
+ "anyhow",
+ "askama 0.12.0",
+ "camino",
+ "cargo_metadata 0.19.0",
+ "clap 4.5.45",
+ "heck 0.5.0",
+ "paste",
+ "serde",
+ "textwrap 0.16.0",
+ "toml 0.8.0",
+ "topological-sort",
+ "uniffi_bindgen",
+ "uniffi_meta",
+]
+
 [[package]]
 name = "uniffi-bindgen-cs"
 version = "0.11.0+v0.31.0"
@@ -4688,6 +4784,12 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df74ff70e2ced9607f67e06640f89a6a6374b459b51bdef290a5cfa657fe4fcc"
 
+[[package]]
+name = "version_check"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2edadb5308f31d97771a678c33df28f18d04f61de3fe21b9452f37854eb6c08"
+
 [[package]]
 name = "version_check"
 version = "0.9.4"