Trying to get to grips with references and joins in DBIx

Let us assume I have the following three Schema classes set up:

A web-based service:

---- file 1 ----
package ORI::Schema::Result::Repo;
extends 'DBIx::Class::Core';
__PACKAGE__->table("repo");
__PACKAGE__->add_columns(
  "id"         => { data_type => "integer" },
  "system_url" => { data_type => "text" },
  "oaibaseurl" => { data_type => "text" },
  "lat"        => { data_type => "real" },
  "long"       => { data_type => "real" },
  "mandate"    => { data_type => "boolean" },
  "fulltext"   => { data_type => "boolean" },
  "openaccess" => { data_type => "boolean" },

);
__PACKAGE__->set_primary_key("id");
__PACKAGE__->has_many(
  "contentlinks" => "ORI::Schema::Result::Contentlink",
  { "foreign.repo_id" => "self.id" },
);
__PACKAGE__->many_to_many("contents", "contentlinks", "content");
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A list of types of content the service deals with (can be multiple data types):

---- file 2 ----
package ORI::Schema::Result::Contenttype;
extends 'DBIx::Class::Core';
__PACKAGE__->table("contenttypes");
__PACKAGE__->add_columns(
  "id"   => { data_type => "integer" },
  "text" => { data_type => "text" },
);
__PACKAGE__->set_primary_key("id");
_PACKAGE__->has_many(
  "contentlinks"         => "ORI::Schema::Result::Contentlink",
  { "foreign.content_id" => "self.id" },
);
__PACKAGE__->many_to_many("repos", "contentlinks", "repo");
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Finally, a table to link web services to data types:

---- file 3 ----
package ORI::Schema::Result::Contentlink;
extends 'DBIx::Class::Core';
_PACKAGE__->table("contentlinks");
__PACKAGE__->add_columns(
  "content_id" => { data_type => "integer" },
  "repo_id"    => { data_type => "integer" },
);
__PACKAGE__->set_primary_key("content_id", "repo_id");
__PACKAGE__->belongs_to(
  "content" => "ORI::Schema::Result::Contenttype",
  { id => "content_id" },
);
__PACKAGE__->belongs_to(
  "repo" => "ORI::Schema::Result::Repo",
  { id => "repo_id" },
);
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So, in code (a Catalyst Controller, in my case), I can get the ORI::Schema::Result::Repo values using the Template Toolkit:

---- within controller ----
    # Get the first 10 results (getting all crashes the system! )
    $c->stash( repos => [ $c->model('ORIdatabase::Repo')->search(
                          {}
                          {
                             rows     => '10'
                          }
                        )
                      ] );

---- In Template ----
[% FOREACH repo IN repos -%]
 <tr>
    <td>[% repo.oaibaseurl %]</td>
    <td>[% repo.system_url %]</td>
    <td>[% repo.lat %]</td>
    <td>[% repo.long %]</td>
    <td>[% repo.opstatus %]</td>
    <td>[% repo.fulltext %]</td>
    <td>[% repo.mandate %]</td>
[% END -%]
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.... but how do I get a list of all the data types the web-service is linked to?

---- within controller ----
    # Get the first 10 results (getting all crashes the system! )
    # Add in a join to get all the contents (ManyToMany relationship)
    $c->stash( repos => [ $c->model('ORIdatabase::Repo')->search(
                          {}
                          {
                             join     => 'contents',
                             prefetch => 'contents',
                             rows     => '10'
                          }
                        )
                      ] );

---- In Template ----
[% FOREACH repo IN repos -%]
 <tr>
    <td>[% repo.oaibaseurl %]</td>
    <td>[% repo.system_url %]</td>
    <td>[% repo.lat %]</td>
    <td>[% repo.long %]</td>
    <td>[% repo.opstatus %]</td>
    <td>[% repo.fulltext %]</td>
    <td>[% repo.mandate %]</td>
    <td>[% repo.mandate %]</td>
    <td>
 [% # How to I get the list of content types? -%]
    </td>
[% END -%]
[download]

.... however this barfs! Using the 'content' or 'contents' relationships fail, and 'contentlinks' just goes down 1 level!!

How do I get the list of text fields from ORI::Schema::Result::Contenttype, where they are linked by ORI::Schema::Result::Contentlink?