feat: ConnectWise PSA integration (#106)

PSA abstraction layer with provider pattern, ConnectWise integration (connection management, ticket linking, note posting, status updates, member mapping), Integrations page UI, Fernet credential encryption, in-memory TTL cache, 6 DB migrations, ConnectWise API reference docs.

docs/connectwise/best-practices/PSA-Cloud-URL-Formatting.md

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+1.  Last updated
+    
+    Apr 8, 2025
+    
+2.  [Save as PDF](https://developer.connectwise.com/@api/deki/pages/959/pdf/PSA%2bCloud%2bURL%2bFormatting.pdf "Export page as a PDF")
+
+When making calls to the ConnectWise PSA API, we have a URL that will give you the exact codebase to target in place of v4\_6\_release.  This is useful to see if someone is on a cloud environment programmatically.  Additionally, the request can be routed directly to the correct PSA version for the partner without it going through another source.
+
+## Calling Company Info
+
+```
+"https://" + ConnectWiseSite + "/login/companyinfo/" + LoginCompanyId
+https://na.myconnectwise.net/login/companyinfo/connectwise
+```
+
+#### Response
+
+```
+{  
+   "CompanyName":"ConnectWise",
+   "Codebase":"v2017_3/",
+   "VersionCode":"v2017.3",
+   "VersionNumber":"v4.6.38842",
+   "CompanyID":"CW",
+   "IsCloud":"True" *Added in 2016.5
+}
+```
+
+## API Request URL Format
+
+```
+"https://" + ConnectWiseSite + "/" + codebase + "apis/3.0/company/companies"
+https://api-my.myconnectwise.net/v2017_3/apis/3.0/company/companies
+```
+
+## Cloud vs Premise
+
+A cloud environment will return a codebase with the PSA version.  On-Premise does not use URL redirection and will return v4\_6\_release/.  If your returned codebase contains anything other than v4\_6\_release/, you will need to ensure your request is prefixed by API-
+
+## Cloud URLs
+
+These are the most commonly used URLs for the cloud.
+
+```
+https://na.myconnectwise.net
+https://eu.myconnectwise.net
+https://au.myconnectwise.net
+https://aus.myconnectwise.net
+https://za.myconnectwise.net
+https://staging.connectwisedev.com
+```