chore: Make jecs a dependency, bump jecs to v0.3.0

+ Make jecs a wally dependency instead of a file in lib. This wasn't done earlier due to wally packages not being able to be used outside of Roblox without dynamically requiring them. Now, a script is used to download the latest source of jecsfrom Github associated with the version in the manifest.

+ Bump jecs-utils to v0.1.3 and release

.lune/download-jecs.luau

@@ -0,0 +1,67 @@
+--!strict
+local fs = require("@lune/fs")
+local net = require("@lune/net")
+local process = require("@lune/process")
+local serde = require("@lune/serde")
+local spawn = require("util/spawn")
+
+type wally_manifest = {
+    package: {
+        name: string,
+        version: string,
+        registry: string,
+        realm: string,
+        license: string?,
+        exclude: { string }?,
+        include: { string }?,
+    },
+    dependencies: {
+        [string]: string,
+    },
+}
+
+local github_token: string = process.args[1]
+
+if not github_token then
+    local env_exists = fs.metadata(".env").exists
+    if not env_exists then
+        error("Usage: lune run download-jecs [GITHUB_PAT]\nAlternatively, put the PAT in an .env file under GITHUB_PAT")
+    end
+
+    local env = serde.decode("toml", fs.readFile(".env"))
+    local pat = env.GITHUB_PAT or error("Couldn't read GITHUB_PAT from .env")
+    github_token = pat
+end
+
+local manifest_contents = fs.readFile("wally.toml") or error("Couldn't read manifest.")
+local manifest: wally_manifest = serde.decode("toml", manifest_contents) or error("Couldn't decode manifest.")
+local jecs_version = string.match(manifest.dependencies.jecs, "%d.%d.%d") or error("Couldn't find jecs version.")
+
+type gh_api_tag = {
+    ref: string,
+    node_id: string,
+    url: string,
+    object: {
+        sha: string,
+        type: string,
+        url: string,
+    },
+}
+
+local response = net.request({
+    url = `https://api.github.com/repos/ukendio/jecs/git/refs/tags/v{jecs_version}`,
+    method = "GET",
+    headers = {
+        Accept = "application/vnd.github+json",
+        Authorization = `Bearer {github_token}`,
+        ["X-GitHub-Api-Version"] = "2022-11-28",
+    },
+})
+
+if not response.ok then
+    error(`Github api response not ok:\n{response.statusCode} @ {response.statusMessage}\n{response.body}`)
+end
+
+local gh_api_tag: gh_api_tag = serde.decode("json", response.body)
+
+spawn.start(`curl https://raw.githubusercontent.com/ukendio/jecs/{gh_api_tag.object.sha}/src/init.luau -o jecs.luau`)