Regenerate docs, update CHANGELOG for v1.0.0, clean up registry manifest

- Regenerated docs/ via tfplugindocs: 51 files covering all 20 resources
  and 30 data sources with auto-extracted schemas and examples
- Removed stale docs for old resources (build.md, ssh.md)
- CHANGELOG.md: added v1.0.0 entry with full feature list, breaking
  changes, and security notes
- terraform-registry-manifest.json: confirmed protocol_versions ["6.0"]
  is correct for Terraform Plugin Framework

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/resources/ip_block_range.md

@@ -0,0 +1,28 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "virtfusion_ip_block_range Resource - virtfusion"
+subcategory: ""
+description: |-
+  Adds an IPv4 address range to a VirtFusion IP block. This is a create-only resource — ranges cannot be deleted via the API.
+---
+
+# virtfusion_ip_block_range (Resource)
+
+Adds an IPv4 address range to a VirtFusion IP block. This is a create-only resource — ranges cannot be deleted via the API.
+
+
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Required
+
+- `end_ip` (String) The ending IP address of the range.
+- `gateway` (String) The gateway address for the range.
+- `ip_block_id` (Number) The ID of the IP block to add the range to.
+- `netmask` (String) The netmask for the range.
+- `start_ip` (String) The starting IP address of the range.
+
+### Read-Only
+
+- `id` (String) The identifier of the IP block range.