docs: add comprehensive documentation and fix github actions

- add docs/ with installation, usage, modules, scans, and api docs
- add docs link to main readme
- fix release.yml to bundle modules directory with releases
- add module system tests to runtest.yml
- standardize go version to 1.23 across workflows

docs/quickstart.md

@@ -0,0 +1,102 @@
+# quickstart
+
+get up and running with sif in minutes.
+
+## basic scan
+
+run a basic scan against a target:
+
+```bash
+./sif -u https://example.com
+```
+
+this performs a base scan checking robots.txt, common files, and basic reconnaissance.
+
+## add more scans
+
+enable additional scan types with flags:
+
+```bash
+# directory fuzzing
+./sif -u https://example.com -dirlist medium
+
+# subdomain enumeration
+./sif -u https://example.com -dnslist small
+
+# port scanning
+./sif -u https://example.com -ports common
+
+# framework detection
+./sif -u https://example.com -framework
+```
+
+## run modules
+
+sif has a modular architecture with yaml-based security checks:
+
+```bash
+# list available modules
+./sif -lm
+
+# run all modules
+./sif -u https://example.com -am
+
+# run specific modules
+./sif -u https://example.com -m sqli-error-based,xss-reflected
+
+# run by tag
+./sif -u https://example.com -mt owasp-top10
+```
+
+## multiple targets
+
+scan multiple urls:
+
+```bash
+./sif -u https://site1.com,https://site2.com
+```
+
+or from a file:
+
+```bash
+./sif -f targets.txt
+```
+
+## save output
+
+save results to a log directory:
+
+```bash
+./sif -u https://example.com -l ./logs
+```
+
+## json output
+
+for automation, use api mode:
+
+```bash
+./sif -u https://example.com -api
+```
+
+## full scan example
+
+run everything:
+
+```bash
+./sif -u https://example.com \
+  -dirlist medium \
+  -dnslist small \
+  -ports common \
+  -framework \
+  -js \
+  -headers \
+  -git \
+  -am \
+  -l ./logs
+```
+
+## next steps
+
+- [usage](usage.md) - all command line options
+- [scans](scans.md) - detailed scan descriptions
+- [modules](modules.md) - write custom modules