Remove the view command and the editor setting with it

`view` was the last user of `editor`, so leaving the setting behind would
have made it exactly what `gitkey` was until recently: documented,
parsed, and doing nothing. It is gone from the struct, the template, the
environment, `config -k` and the settings table.

Both names are free for aliases now, as `open` already was.

The tests that used `editor` as their example of a project-overridable
setting use `gitkey` instead, which is the same kind of thing and still
exists.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -40,7 +40,7 @@ stand in. Outside `base` no project is selected. `mgsh <project>` starts the
 interactive shell with that project preselected.
 
 The commands available directly from the shell are `clone`, `init`, `log`,
-`push`, `pushremote`, `release`, `list`, `tag`, `archive`, `show`, `view`,
+`push`, `pushremote`, `release`, `list`, `tag`, `archive`, `show`,
 `pull`, `fetch`, `status`, `diff`, `overview`, `config`, `count`, `login` and
 `cloneall`; every other command is interactive-only.
 
@@ -52,7 +52,7 @@ project, its git branch and a `*` dirty marker:
 ```
 
 Features: command history (`~/.mgsh_history`), Tab completion (commands, local
-projects for `cd`/`view`, server repos for `clone`/`show`, branches/tags for
+projects for `cd`, server repos for `clone`/`show`, branches/tags for
 `checkout`/`tag`, mirror targets for `pushremote`/`release`, filesystem paths for
 `dist`, and shell-style completion after `!` and for aliases that expand to
 one), and colored `list`/`log`/error output.
@@ -106,7 +106,6 @@ Run `help` for the full list. Highlights:
 | command                   | description                                    |
 |---------------------------|------------------------------------------------|
 | `cd [project]`            | change project (no argument: back to the base) |
-| `view [project]`          | open a project in Xcode / the configured editor |
 | `push [comment]`          | commit everything and push to the server       |
 | `pushremote [desc]`       | mirror the repo to a public server (gitea/github/gitlab) |
 | `pull` / `fetch`          | pull / fetch from the server                   |
@@ -145,7 +144,6 @@ project /Users/me/src/myproject/.mgshrc
   gitport       22
   gituser       git
   gitpath       /home/git
-  editor        code  (.mgshrc)
   remotes       hub  (.mgshrc)
   clone url     ssh://git@git.example.com:22/home/git
 
@@ -410,7 +408,6 @@ gitpath     = /home/git
 gitname     = Your Name
 gitemail    = you@example.com
 pushdefault = matching
-editor      = code            # fallback opener for `view`
 
 alias co 'checkout $1'
 ```
@@ -436,7 +433,6 @@ setting.
 | `gitname` | global | `user.name` written to the **global** git config at startup |
 | `gitemail` | global | `user.email` written to the global git config |
 | `pushdefault` | global | `push.default` written to the global git config |
-| `editor` | project | opener used by `view` when the project has no Xcode workspace (default `coda`) |
 | `remote.<name>.url` | project | base URL of the mirror target `<name>` |
 | `remote.<name>.key` | project | API token for that target |
 | `remote.<name>.type` | project | `gitea`\|`github`\|`gitlab`; auto-detected from the url when unset |
@@ -453,7 +449,7 @@ only when they actually differ, so a plain `mgsh status` does not rewrite
 
 A project may carry its own `.mgshrc`, which overrides the global settings while
 that project is active — a project on a different git server, with a different
-editor, or mirrored to a different place:
+ssh identity, or mirrored to a different place:
 
 ```ini
 # ~/src/myproject/.mgshrc