feat: Add operating system module (#4109)

* docs(os): Add os module documentation

* docs(os): Add os to Default Prompt Format

* chore(os): Update config file schema

* feat(os): Add os entries and declarations

* feat(os): Add os module and config

* fix(os): Obey config.disabled

* feat(os): make variables 'Unknown'-aware

refactor(os): calculate variables in dedicated functions

* test(os): Add os module tests

* feat(os): make 'name' variable less 'Unknown'-aware

* docs(os): Add Preset configurations

docs(os): Use emoji as default

* feat(os): Use emoji as default

test(os): Use emoji as default

* fix(os): Add spaces after emoji symbols

* chore(os): Update config schema

* feat(os): Remove `bitness` variable

docs(os): Remove `bitness` variable

test(os): Remove `bitness` test

* feat(os): Add Cargo.toml upgrade caution for os_info

* refactor(os): Clarify get_symbol function

* docs(os): Mention supported operating systems and feature requests

* docs(os): Mention os_info inacurracy

* test(os): Remove `bitness` leftovers

* refactor(os): use nu_ansi_term

* refactor(os): add cfg_attr(schemars(deny_unknown_fields))

* chore(os): update config schema

* docs(os): expose details block

* feat(os): add garuda linux

* chore(os): update config schema

* feat(os): add case insensitivity

* feat(os): add symbols `IndexMap` use `os_info::Type` instead of `String`

* test(os): add clippy warn on new os_info::Type case

* leave missing case to test github tests

* test(os): re-add missing test case

* style(os): fix formatting

* docs(os): update to match os_info::Type serialization

- docs(os): add missing garuda to config

- test(os): mention docs updates in warn_on_os_info_update

.github/config-schema.json

@@ -1027,6 +1027,56 @@
         }
       ]
     },
+    "os": {
+      "default": {
+        "disabled": true,
+        "format": "[$symbol]($style)",
+        "style": "bold white",
+        "symbols": {
+          "Alpine": "🏔️ ",
+          "Amazon": "🙂 ",
+          "Android": "🤖 ",
+          "Arch": "🎗️ ",
+          "CentOS": "💠 ",
+          "Debian": "🌀 ",
+          "DragonFly": "🐉 ",
+          "Emscripten": "🔗 ",
+          "EndeavourOS": "🚀 ",
+          "Fedora": "🎩 ",
+          "FreeBSD": "😈 ",
+          "Garuda": "🦅 ",
+          "Gentoo": "🗜️ ",
+          "HardenedBSD": "🛡️ ",
+          "Illumos": "🐦 ",
+          "Linux": "🐧 ",
+          "Macos": "🍎 ",
+          "Manjaro": "🥭 ",
+          "Mariner": "🌊 ",
+          "MidnightBSD": "🌘 ",
+          "Mint": "🌿 ",
+          "NetBSD": "🚩 ",
+          "NixOS": "❄️ ",
+          "OpenBSD": "🐡 ",
+          "OracleLinux": "🦴 ",
+          "Pop": "🍭 ",
+          "Raspbian": "🍓 ",
+          "RedHatEnterprise": "🎩 ",
+          "Redhat": "🎩 ",
+          "Redox": "🧪 ",
+          "SUSE": "🦎 ",
+          "Solus": "⛵ ",
+          "Ubuntu": "🎯 ",
+          "Unknown": "❓ ",
+          "Windows": "🪟 ",
+          "openSUSE": "🦎 "
+        }
+      },
+      "allOf": [
+        {
+          "$ref": "#/definitions/OSConfig"
+        }
+      ]
+    },
     "package": {
       "default": {
         "disabled": false,
@@ -3989,6 +4039,68 @@
       },
       "additionalProperties": false
     },
+    "OSConfig": {
+      "type": "object",
+      "properties": {
+        "format": {
+          "default": "[$symbol]($style)",
+          "type": "string"
+        },
+        "style": {
+          "default": "bold white",
+          "type": "string"
+        },
+        "symbols": {
+          "default": {
+            "Alpine": "🏔️ ",
+            "Amazon": "🙂 ",
+            "Android": "🤖 ",
+            "Arch": "🎗️ ",
+            "CentOS": "💠 ",
+            "Debian": "🌀 ",
+            "DragonFly": "🐉 ",
+            "Emscripten": "🔗 ",
+            "EndeavourOS": "🚀 ",
+            "Fedora": "🎩 ",
+            "FreeBSD": "😈 ",
+            "Garuda": "🦅 ",
+            "Gentoo": "🗜️ ",
+            "HardenedBSD": "🛡️ ",
+            "Illumos": "🐦 ",
+            "Linux": "🐧 ",
+            "Macos": "🍎 ",
+            "Manjaro": "🥭 ",
+            "Mariner": "🌊 ",
+            "MidnightBSD": "🌘 ",
+            "Mint": "🌿 ",
+            "NetBSD": "🚩 ",
+            "NixOS": "❄️ ",
+            "OpenBSD": "🐡 ",
+            "OracleLinux": "🦴 ",
+            "Pop": "🍭 ",
+            "Raspbian": "🍓 ",
+            "RedHatEnterprise": "🎩 ",
+            "Redhat": "🎩 ",
+            "Redox": "🧪 ",
+            "SUSE": "🦎 ",
+            "Solus": "⛵ ",
+            "Ubuntu": "🎯 ",
+            "Unknown": "❓ ",
+            "Windows": "🪟 ",
+            "openSUSE": "🦎 "
+          },
+          "type": "object",
+          "additionalProperties": {
+            "type": "string"
+          }
+        },
+        "disabled": {
+          "default": true,
+          "type": "boolean"
+        }
+      },
+      "additionalProperties": false
+    },
     "PackageConfig": {
       "type": "object",
       "properties": {