Build Docker images from source (#1877)

* fix(docker): build images from source

Collapse the npm-install and source-build image paths into one Dockerfile so every Docker image is built from the checked-out workspace packages. Include procps in the runtime image because provider process cleanup depends on ps through tree-kill on Linux.

* fix(docker): include native speech packages

* fix(docker): cover source build inputs

* fix(docker): ignore local agent artifacts

.dockerignore

@@ -1,11 +1,31 @@
 .git
+.debug.conversations
+.debug
 .dev
 .playwright-mcp
+**/.playwright-mcp
 .paseo
+**/.paseo-provider-history
+.plans
 .tasks
+.valknut
+.claude/settings.local.json
+**/.claude/settings.local.json
+.claude/scheduled_tasks.lock
+.claude/worktrees
 .wrangler
 **/.wrangler
 **/.tanstack
+PLAN.md
+valknut-report.html
+valknut-report.json
+.env*
+**/.env*
+.dev.vars
+**/.dev.vars
+*.pem
+**/*.pem
+**/.secrets
 **/node_modules
 **/dist
 **/build