Massive architectural rework

This commit massively overhauls the project's structure to simplify
development. Most parts are now correctly compartmentalized and
dependencies are passed in a sane way rather than global variables
galore xd.

internal/handlers/schema.sql

@@ -0,0 +1,28 @@
+CREATE TABLE IF NOT EXISTS deployments (
+    id INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE,
+    url TEXT NOT NULL UNIQUE,
+    port INTEGER NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS apps (
+    id BLOB PRIMARY KEY,
+    name TEXT NOT NULL UNIQUE,
+    deployment_id INTEGER,
+    FOREIGN KEY(deployment_id) REFERENCES deployments(id)
+);
+
+CREATE TABLE IF NOT EXISTS containers (
+    id INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE,
+    container_id TEXT NOT NULL,
+    head BOOLEAN NOT NULL,
+    deployment_id INTEGER NOT NULL,
+    FOREIGN KEY(deployment_id) REFERENCES deployments(id)
+);
+
+CREATE TABLE IF NOT EXISTS volumes (
+    id INTEGER PRIMARY KEY AUTOINCREMENT UNIQUE,
+    volume_id TEXT NOT NULL,
+    mountpoint TEXT NOT NULL,
+    container_id INTEGER NOT NULL,
+    FOREIGN KEY(container_id) REFERENCES containers(id)
+);