[grampsweb] Remove ollama_host source refs (apply blocked by bd-w97)

## Context
Stage 4 of ollama decommission. `grampsweb` referenced `var.ollama_host` for
its `GRAMPSWEB_LLM_BASE_URL` + `GRAMPSWEB_LLM_MODEL` env vars. This stack is
currently missing from Terraform state (blocked by bd-w97, which handles
state imports for 11 stacks including grampsweb) — so an apply would fail on
"resource already exists" errors.

## This change
- Deletes `variable "ollama_host"` declaration (stacks/grampsweb/main.tf).
- Deletes the two env entries `GRAMPSWEB_LLM_BASE_URL` and
  `GRAMPSWEB_LLM_MODEL` from the `common_env` locals block.
- **Source-only** — NO apply performed, because the stack cannot apply
  cleanly until bd-w97 resolves state imports. When that unblocks, the next
  apply will pick up the already-clean source.

## Why not apply now
- Running `scripts/tg apply` would try to create ~7 resources that already
  exist in K8s (namespace, PVCs, deployments, ingress, etc.), producing
  "already exists" errors for each.
- Once bd-w97 imports those into state, the next apply will be a no-op for
  them and will rollout the LLM env-var removal without issue.

## Test plan
### Automated
- No apply performed — stack blocked on bd-w97.
- `terraform fmt` on main.tf: no issues.

### Manual Verification
After bd-w97 resolves:
1. `scripts/tg plan` should show only the env-var removal on `grampsweb`
   deployments (no resource creates).
2. `scripts/tg apply` → deployments rollout with `GRAMPSWEB_LLM_*` vars gone.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

stacks/grampsweb/main.tf

@@ -43,7 +43,6 @@ locals {
   mailserver_accounts = jsondecode(data.kubernetes_secret.eso_secrets.data["mailserver_accounts"])
 }
 variable "redis_host" { type = string }
-variable "ollama_host" { type = string }
 variable "mail_host" { type = string }
 
 
@@ -147,14 +146,6 @@ locals {
       name  = "GRAMPSWEB_DEFAULT_FROM_EMAIL"
       value = "info@viktorbarzin.me"
     },
-    {
-      name  = "GRAMPSWEB_LLM_BASE_URL"
-      value = "http://${var.ollama_host}:11434/v1"
-    },
-    {
-      name  = "GRAMPSWEB_LLM_MODEL"
-      value = "llama3.1"
-    },
   ]
 }