Add build script, generate man page at build-time

Cargo.lock

@@ -88,6 +88,7 @@ dependencies = [
  "avt",
  "axum",
  "clap",
+ "clap_mangen",
  "config",
  "futures-util",
  "mime_guess",
@@ -335,6 +336,16 @@ version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "702fc72eb24e5a1e48ce58027a675bc24edd52096d5397d4aea7c6dd9eca0bd1"
 
+[[package]]
+name = "clap_mangen"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e1dd95b5ebb5c1c54581dd6346f3ed6a79a3eef95dd372fc2ac13d535535300e"
+dependencies = [
+ "clap",
+ "roff",
+]
+
 [[package]]
 name = "clipboard-win"
 version = "5.1.0"
@@ -1642,6 +1653,12 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "roff"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b833d8d034ea094b1ea68aa6d5c740e0d04bad9d16568d08ba6f76823a114316"
+
 [[package]]
 name = "rust-embed"
 version = "8.2.0"