chore: add AGPL3-or-later license

This CL adds the AGPL3-or-later license for all public code.

It also adds some configuration so we can use headroom to automatically
generate the license headers.

GitOrigin-RevId: 634827ab248c207e6841dbad29f59aeadcbef541
diff --git a/.headroom.yaml b/.headroom.yaml
new file mode 100644
index 0000000..77b3c10
--- /dev/null
+++ b/.headroom.yaml
@@ -0,0 +1,38 @@
+## This is the configuration file for Headroom.
+## See https://github.com/vaclavsvejcar/headroom for more details.
+
+version: 0.5.0.0
+
+run-mode: add
+
+source-paths:
+  - src/
+  - upgradescripts/
+
+excluded-paths:
+  - '\/internal\/'
+  - '\/node_modules\/'
+  - '\/lib\/'
+
+exclude-ignored-paths: true
+
+template-paths:
+  - .headroom-templates
+
+license-headers:
+  php:
+    margin-bottom-code: 1
+    put-after:
+      - '^<\?php$'
+    block-comment:
+      starts-with: '^\/\*'
+      ends-with: '\*\/$'
+  js:
+    block-comment:
+      starts-with: '\/\* \(license-header\)'
+      ends-with: '\*\/$'
+
+variables:
+  project: 'hores'
+  year: '{{ _current_year }}'
+  author: 'Adrià Vilanova Martínez'